'O. \ V. ^^ -^^ .^ • V •^4 ^i^ ^^^ ^ V %^ ^;,-^^ % — .^^ .^^ <^ q.. ^^' ..^ w rCES, ETC. ETC ETC. TR\NSLArMF^^'fUE FRENCH. WITH NOTES AND ADDITIONS, BY H. M'MURTRIE, M.D. &c. &c. IN FOUR VOLUMES, WITH PLATE.'u VOLUME III. NEW YORK: G & C. & H. CARVILL MDCCCXXXl. Entered according to the act of congress, in the year one thousand eight hundred and thirty-one, by G. & C. & H. Carvill, in the clerk's oflBce of the southern district of New York. Philadelphia : Printed by James Kay, Jun. & Co. Printers to the American Philosophical Society. No. 4, Minor Street. PREFACE(l). Overwhelmed with scientific laboui'S, and yielding, perhaps too easily, to the impulse of friendship and to my desire to serve him, M. Cuvier has confided to me that portion of this work which treats of Insects. These animals were the objects of his earliest zoological studies, and the cause of his connexion with one of the most celebrated pupils of Linnaeus, Fabricius, who in his writings gives him frequent assurance of his high esteem. It was even by various interesting observations on several of these ani- (1) This preface is the same which stood at the commencement of the third volume of the first edition of this work. Having- there confined myself to an ex- position of the general principles, upon which my arrang-ement of the animals composing the Linnsan class of Insects was effected, and having in the present edition made no change in that respect, the same observations are still applicable. Considered however with regard to the details, or to the secondary and tertiary divisions, that is to saj'. Orders, Families, Genera and Subgenera, this edition will be found to present a remarkable difference. It was impossible to place it on a level with the actual state of the science, without modifying several parts of my former system, and without considerable additions, which, such has been the pro- gress of Entomology, are so numerous, that even by filling- two volumes instead of one, I have been barely enabled to give a very summary view of the multitude of generic divisions effectuated within the last ten years, and which are frequently founded on the most minute characters. This branch of Zoology has gained much from other and more positive sources, those of Anatomy. These observations I was the moi'e imperatively bound to notice, as they formed part of the plan of the illustriousauthor of the "llegne Animal," and as they serve to confirm the stability of the divisions I have established. By a perusal of tlie general remarks which precede them, the reader will be better able to appreciate the motives which have determined these changes, and to feel the importance of the addenda that enrich the entomological portion of this edition. A simple comparison between it and that of the former will show, at a glance, that it has been entirely remoulded, or that it is a new work which we now present to the world, rather than a new edition. IV PREFACE. mals — Journal d^Hist. JVat, — that M. Cuvier commenced his career in natural history. Entomology, in common with all the other branches of Zoology, has derived the greatest advan- tage from his anatomical researches, and the happy changes he has effected in the basis of our classification. The internal or- ganization of Insects is now better known, and this study is no longer neglected as was previously the case. He has placed us on the way to the Natural System(l), and greatly will the public regret that his numerous occupations did not allow him to superintend this portion of his treatise on animals. Perhaps the desire of associating my name with his in a work like this, which, by the multitude of researches on which it rests, and by their application, has become a precious literary monument of the age, has deceived me and thrown me into an enterprize beyond my powers to accomplish. The responsibility is great, and I have imposed upon myself a task, in which the boldness of the plan is only equalled by the dif- ficulty of its execution. To unite within a very limited space the most interesting facts in the history of Insects, to arrange them with precision and clearness in a natural series, to pour- tray with a bold pencil the physiognomy of these animals, trace their distinguishing characters with truth and brevity, in a way proportioned to the successive progress of the science and that of the pupil, to indicate useful or noxious species, and those whose mode of life interests our curiosity, to point out the best sources from which the knowledge of others may be obtained, to restore to Entomology the amiable simplicity which it possessed in the days of Linnaeus, Geoffrey, and of the early writings of Fabricius, but still to present it as it now is, or with all the wealth of observation it has since acquired, yet without overloading it j in a word, to conform to the mo- del before me, the work of M. Cuvier, is the end I have striven to attain. This savant, in his '^Tableau Elementaire de FHistoire Na- turelle des Animaux,'' did not restrict the extent given by (1) Tableau Element, de I'llist. Nat. des Anunaus, and the Leg. d'Anat. Compar. PREFACE, V Linnaeus to his class of Insects ; he however made some necess ary ameliorations, which have since served as the foundation of other systems. He distinguishes Insects, in the first place, from other invertebrate animals, by much more rigorous cha- racters than those previously employed, viz. a knotted medul- lary spinal man'ow, and articulated limbs, Linnaeus termi- nates his class of Insects with those which are apterous, although most of them, such as the Crustacea and the Ara- 7ieides, with respect to their organization, are the most per- fect of their class or are the most closely approximated to the Mollusca. His method, in this respect, is then exactly the inverse of the natural system, and by transporting the Crus- tacea to the head of the class, and by placing almost all the Aptera of Linnaeus directly after them, Cuvier rectified the method in a point where the series was in direct opposition to the scale formed by Nature. In his Legons d'' Anatomic Comparee, the class of Insects, from which he now separates the Crustacea, is divided into nine orders, founded on the nature and functions of the or- gans of manducation, the presence or absence of wings, their number, consistence, and the manner in which they are reti- culated. It is in fact a union of the system of Fabricius with that of Linnaeus perfected. The divisions made by our savant in his first order, that of the Gnathaptera, are nearly similar to those I had established in a Memoir presented to the Societe Philomatique, April 1795, and in my Precis des Caracteres Gemriques des In- sect es{l). M. de Lamarck, whose name is so dear to the friends of natural science, has ably profited by these various labours. His systematic arrangement of the Linnaean Aptera appears to us to be that which approaches nearest to the natural order, and, with some modifications of which we are about to speak, is the one we have followed. (1) I there divided Uie Apteraof Linnaeus into seven orders: 1. The Suctohia. 2. The Thisanocra. 3. The Parasita. 4. The Acephala {Arachnides pal- pistes,lu2Si\.). 5. The Entomostraca. 6. The Crustaciia. r. The Mikiapoba. Vi PREFACE. I divide tlie Insects of LinnaeuSj with him. into three classes: the C?'ustacea, AracJmides ?a\(ii Insecta: but in the essential characters whicii I assign to tliem, I abstract all the changes experienced by these animals, prior to their adult state. This consideration, although natural, and previously employed by De Geer in his arrangement of the Aptera, is not classical, inasmuch as it supposes the observation of the animal in its different ages ; it is, besides, liable to many ex- ceptions(l). The situation and form of the branchise, the manner in which the head is united to the thorax, and the organs of man- ducation, have furnished me the means of establishing seven orders in the class of the Crustacea, all of which appear to me to be natural. I terminate it, with M. de Lamarck, by the Branchiopoda, which are a sort of Crustacea Arachnides. In the following class, that of the Arachnides, I only in- clude the species which in the system of Lamarck, compose the order of his Arachnides palpistes, or those whicli have no antennLC. Beyond this, the organization of these animals, external as well as internal, furnishes us with a simple and rigorous rule that is susceptible of a general application. Their organs of respiration are always internal, receiving air through concentrated stigmata, sometimes possessing func- tions analogous to those of lungs, and consisting at others of radiated tracheae, or such as ramify from their base; the an- tennae are wanting, and they are usually furnished with eight feet. I divide this class into two orders: the Pidmonarix and the Trachearise. Two parallel trachea^,, extending longitudinally through the body, furnished at intervals with centres of branches corres- (1) These considerations, however, have not been overlooked, and I have used them advantageously in grouping' families, and arranging them in a natural order, as may be seen by a reference to the historical skctclies which precede the expo- sition of those famihes. I have even been employed on a work respecting the metamorphosis of Insects in general, which has not yet been published (see article "Insectes," Nouv. Diet. d'Hlst. Nat. Ed. 2d), but which I have long been matur- ing, and which I have communicated to my friends: I have made use of it in the course of my general remarks. PREFACE. Vll ponding to the stigmata, and two antennte, characterize the class of Insects. Its primary divisions are founded on the three following considerations : 1 . Apterous Insects which either imdei'go no metamorpho- ses, or but imperfect ones ; the three first orders. 2. Apterous Insects which experience co?npIete transfor- mations ; the fourth. 3. Insects having wings which they acquire by metamor- phoses, either complete or incomplete ; the last eight. I begin with the .Irachnides antennistes of jM. de Lamarck, which arc comprised in this first division, and which form our three firet orders. The second is composed of the fourth order, and contains but a single genus, that of Pulex : it would appear, in some respects, to be allied to the Diptera by means oi the Ilippoboscx ; other characters however, and the na- ture of its metamorphoses, remove this genus from that of the HippobosciB. It is very difiicult in some cases to distinguish these natural filiations, and when we are fortunate enough to discover them, we are frequently compelled to sacrifice them to the perspicuity and focility of the system. To the known order of winged Insects, I have added that of the Siresiptcra of Kirby, but under a new denomination, viz. that of Bhipiptcraj as the former appears to me to be founded on a false idea. Perhaps we should even suppress this order, according to the opinion of Lamarck, and unite it with that of the Diptera. For reasons elsewhere developed(l), and which I could easily strengthen by additional proof, I attach more conse- quence to characters drawn from the aerial locomotive organs of Insects, and to the general composition of their body, than to the modifications of the parts of the mouth, at least when their structure is essentially referable to the same type. Thus I do not connnence by dividing these animals into Grinders and Suckers J but into those which have wings and wing-cases, and such as have four or two wing-s of the same consistence. The form and uses of the organs of manducation are viewed (1) Consid. GciKT. sviv rorJre dcs Crust., des Arach., et des Insectes, p. 46. Vlll PREFACE. in a secondary light. My series of Orders relative to the winged Insects is, consequently, nearly similar to that of Linnaeus. Fabricius, Cuvier, Lamarck, Clairville and Dumeril, con- sidering the difference of the functions of the parts of the mouth of primary consequence, have arranged those divisions otherwise. In accordance with the plan of M. Cuvier, I have reduced the number of families which I established in my previous works, and have converted into subgenera the numerous divi- sions that have been made of the genera of Linnaeus, notwith- standing their characters may otherwise be very distinct. Such also was the intention of Gmelin in his edition of the Systejna A\iturse. This method is simple, historical and convenient, as it enables the student to proportion his instruc- tion to his age, his capacity, or to the end he has in view. All my groups are founded on a comparative examination of all the parts of the animals I wish to describe, and on the observation of their habits. Most Naturalists stray from the natural system by being too exclusive in their considerations. To the facts collected by Reaumur, Roesel, De Geer, Bonnet, the Hubers, &c. respecting the instinct of Insects, I have added several ascertained by myself, some of which were hitherto unknown. M. Cuvier has added to them an extract of his anatomical observations(l); he has even devoted himself to fresh researches, among which I will mention those whose object was the organization of the Lirauli, a very singular genus of the Crustacea. Being necessarily restricted in the description of species, I have always selected for that purpose the most interesting and common ones, and particularly those mentioned by M. Cuvier in his Tableau Elementaire de PHistoire Naturelle des Animaux. LATREILLE. (I) Those added to the present edition are from Messrs Leon Dufour, Marcel de Serres, Straus, Audouin and Milne Edwards, SYSTEMATIC INDEX. ARTICULATA with arti- culated FEET. 1 CLASS I. CRUSTACEA 6 Their division into orders 9 MALACOSTRACA 12 a. Eyes placed on a mova- ble and articulated pe- dicle 12 DEC APOD A 13 BRACUYURA 20 Cancer 21 Pinnipedes 21 Matuta 22 Polybius . 22 Orythyia 23 Podopthalmus 23 Portunus 24 Platyonichus 25 Arcuata 26 Cancer proper 26 Clorodius 27 Carpilius 27 Xantho{\) 27 Pirimela 27 Atelecyclus 27 Thia 28 Mursia 28 Hepatus 29 Quadrilatera 29 Eriphia 30 Trapezia 30 Pilumnus 30 Thelphusa 30 Gonoplax 32 Macropthalmus 32 Gelasimus 33 Ocypode 34 Mictyris 35 Pinnotheres 35 Uca 36 Cardisoma 37 Gecarcinus 37 Pla^usia 38 Grapsus 38 Orbiculata 39 Coyystes 39 Leucosia 39 Ixa 40 Iphis 40 Nursia 40 Arcania 40 Ilia 40 Persephona 40 Myra 40 Leucosia 40 Phylira 40 Ebalia 41 Trigona 41 Parthenope 42 Lambrus 42 Mithrax 43 Acanthonyx 43 Pisa 43 Pericera 43 Mai a 44 Micippe 44 Stenocionops 44 • Camposcia 45 Halimus 45 Hyas 45 Libinia 46 Doclsea 46 Egeria 46 Leptopus 47 Hymenosoma 47 Inachus 48 Achxus 48 Stenorhynchus 48 Leptopodia 48 (1) Those genera which we mention accessorily, either because they are but slightly or not at all known to us, or because we unite them with others, are printed in italics. Vol. Ill — (2) SYSTEMATIC INDEX. Pactolu3 . 49 Lithodes 49 Cryptopoda 49 Calappa 49 iEthra 49 Notopocla 51 Ilomola 51 Doi-ippe 51 Dromia 52 Dynomene 52 Ranina 52 MACROURA 54 Astacus 55 Anomala 55 Albunea 56 Hippa 56 Remipes 57 Birgus 58 Pag-urus 58 Csenobita 58 Pagurus 59 Prophylax 59 Locusiae 60 Scyllarus 60 Ttienus 61 Ibacus 61 Paliniirus 61 Astacini 62 Galathea 63 Grirnoiea 63 Munida 63 Slglea 64 Janira 64 Porcellana 64 Monolepis 65 Megalopus 65 Gebia 6& Thalasslna 66 Callianassa 66 Axius 67 Eryon 67 Astacus proper 67 Nephrops 68 Carides 69 Penaeus 70 Stenopus 71 Atya 71 Crangon 71 Processa 73 Hymenocera 73 Gnathophyllum 75 Pontonia 73 Alpheua 7:i Hyppolite 74 Autonomera 74 Pandalus 74 Palscmon 74 Lysmata 75 Athanas 75 Pasiphsea 76 Mysis 76 Ciyptopus 77 Miilcion 77 STOMAPODA 77 UNIPELTATA 81 Squilla 82 Squilla proper 82 Gonodactylus 83 Coronis 83 Erichthiis 83 Alima 84 BIPELTATA 84 Phyllosoma 84 (3. Eyes sessile and immoi - able 85 AMPHIPODA 87 Gammarus 87 Phronima 88 Hyp aria 88 Phrosine 89 Dactylocera 89 lone 90 Orchestia 91 Taliprus 91 Atylus 91 Gammarus proper 92 Melita 92 y Msera 92 Amphlthoe 92 Pherusa 92 Dexamine 93 Lencothoe 93 Cerapus 93 Podocerus 93 Jassa 93 Corophium 94 Pterygocera 94 Apseudes 95 Typhis 95 Anceus 95 Praniza 96 Ergine 96 LiEMODIPODA 96 Cyamus 97 Leptomera 97 Naupredia 98 Caprella 98 Cyamus proper 98 ISOPODA 99 Oniscus 100 Bopyrus 101 Scrolls 101 Cymothoa 102 Ichthyophilus 102 Nerocila 102 Livoneca 102 Canolira 102 ^ga 103 Rocinela 103 Conilira 103 Synodus 103 SYSTEMATIC INDEX. XI Nelocira 103 Eurydice 103 Limnoria 104 Zuzara 105 Sphacroma 105 Naesa 105 Campecopea 105 Cilicasa 105 Cymodocea 106 Dynamene 106 Anthiira 106 Idotsea 106 Stenosoma 107 Arcturus 107 Asellus 107 Oniscoda 108 Jaera 108 Tylos 108 Ligia 109 Philoscia 109 Onisciis proper 110 Porcellio 110 Armadillo 110 ENTOMOSTRACA 112 BRANCHIOPODA 114 Monoculus 115 Lophyropa 115 Zoea 117 Neb alia 117 Condylura 118 Cyclops 119 Cythere 122 Cypris - 122 Sida 125 Latona 125 Polyphemus 126 Daphnia 127 Lynceus 132 Phyllopa 132 Limnadia 133 Artemia 134 Branchipus • 134 Eulimene 137 Apus 138 Lepidurus 141 PjECILOPODA 141 XYPHOSURA 142 Limulus 142 Tachypleus 145 SIPHONOSTOMA 146 CALLIGIDES 146 Argulus 147 Caligus 150 Caligus proper 151 Pterygopoda 151 Pandarus 151 Dinemoura 151 Anthosoma 152 Cecrops 152 LERNEIFORMES 152 Dichelestium 153 Nicothoe 154 TRILOBITES 155 Agnostus 157 Calymene 157 Asaphus 157 Ogygia 157 Paracloxides 157 CLASS II. ARACHNIDES 159 PULMONARI^ 162 ARANEIDES 164 Mygale 173 Mygale proper 174 Cteniza 175 Atypus 177 Eriodcn 178 Dysdera 179 Filistata 179 Aranea 179 Tubitelae 180 Clotho 180 Drassus 182 Segestria 183 Clubiona 183 Aranea proper 184 Ai'gyroneta 184 Inequitelae 184 Scytodes 185 Theridion 185 Episinus 186 Pholcus 186 Orbitelae 186 Linyphia 187 Ulobonis 187 Tetragnatha 188 Epeira 188 Laterigradse 191 Micrommata 191 Senelops 192 Pliilodromus 193 Thomisus 194 Storena 195 Citigradae 196 Oxyopes 196 Ctenus 196 Dolomedes 197 Lycosa 197 Myrmecia 199 PEDIPALPI 202 Tarantula 202 Phrynus 202 Thelyphonus 203 Scorpio 203 TRACHEARI^ 206 PSEUDO-SCORPIONES 207 Galeodes 208 Chelifer 209 xn SYSTEMATIC INDEX. PYCNOGONIDES 210 Pycnogonum 211 Phoxichilus 211 Nymphon 211 Ammothea 2 1 1 HOLETRA 212 Phalaxgita 212 Phalangium 213 Gonoleptes 2 1 3 Siro 214 Macrocheles 214 Trogulus 214 ACARIBES 214 Acarus 214 Trombidium 215 Erythrxus 215 Gamasus 215 Cheyletus 216 Oribata 216 Uropoda 216 Acarus proper 217 Bdella 217 Smaridia 217 Ixodes 218 Argas 219 Eylais 219 Hydrachna 219 Limnochares 220 Caris 220 Leptus 220 Aclysia 220 Atoma 221 Ocypete 221 CLASS III. INSECTA 229 MYRIOPODA 245 CHILOGNATHA 247 lulus 249 Glomeris 250 lulus proper 250 Polydesmus 251 Pollyxenus 251 CHILOPODA 251 Scolopendra Scutigera Lithobius "2 Scolopendra proper 2 THYSANOURA o. LEPISMEN^ Lepisma 255 MachlUs 256 Lepisma proper 256 PODURELL^ 256 Podura 257 Podura proper 257 Smynthurus 257 PARASITA 258 Pediculus 258 253 253 :54 55 255 Pediculus proper 258 Haematoplnus 260 Ricinus 260 TricJiodedes 261 Gyropus 261 Liotheum 261 Philopterus 261 Goniodes 262 TriotiguUn 262 SUCTORIA 262 Pulex 263 COLEOPTERA 264 Pentamera. CARNIVORA 266 TRIBE I. Cicindelet;e 269 Cicindela 269 Afanticora 269 Megacephala 270 Oxycheila 270 Euprosopus 270 Cicindela proper 270 Ctenostoma 272 Therates 272 CoUiuris 273 Tricondyla 273 TRIBE II. Cababici 273 Carabus 274 Truncatipennes 274 Anthia 275 Graphipterus 275 Aptinus 276 Brachinus 276 Corsyra 277 Casnonia 278 Leptotrachelus 278 Odacantha 278 Zuphium 279 Polistichus 279 Helluo 279 Drypta 280 Trichognatha 281 Galerita 281 Cordistes 281 Ctenodactyla 282 Agra 282 Cymindis 282 Calleida 283 Demetrias 283 Dromias 283 Lebia 283 Plochionus 284 Orthogonius 284 Coptodera 284 Bipartiti 284 Enceladus 285 Siagona 285 Carenum 286 Pasimachus 287 SYSTEMATIC INDEX. Xlll Acanthoscelis 287 Licinus 307 Scarites 288 Badister 307 Oxj'gnathus 289 Pelecium 308 Oxystomus 289 Cynthia 308 Camptodontus 289 Panagaeus 308 Clivina 290 Loricera 309 Dischirius 290 Patrobus 309 Morio 290 Grandipalpi 310 Ozsena 290 Pamborus 310 Ditomus 291 Cychrus 310 dristus 291 Scaphinotus 31t Apotomus 291 Sphseroderus 311 Quadrimani 291 Tefflus 311 Acinopus 292 Procerus 311 Daptus 293 Procrustes 312 Ilarpalus 293 Carabus proper 312 Ophonus 294 Plectes 312 Stenolophus 294 Cechenus 312 Acupalpus 294 Calosoma 313 Simplicimani 294 Pogonophorus 315 Zabrus 296 Nebria 315 Pogonus 296 Alpjeus 315 Tetragonoderus 297 Omophron 316 Feronia 297 Elaphrus 316 JLmara 297 Blethisa 316 Paecilus 297 Pelopkilus 316 Argutor 297 Notiophilus 317 Omaseus 297 Subulipalpi 317 Flatysma 297 Bembidium 318 Pterostichus 297 Tachypus 318 Max 297 Lopha 318 Steropus 297 Notaphus 318 Percus 297 Peryphus 318 Molops 297 Leja 318 Cophosus 297 Trechus 319 Cheporus 299 Blemus 319 My as 300 TRIBE III. Trig-onomota 300 Hydrocastthahi 319 Pseudo-morpha 300 Dytiscus 320 Cephalotes 301 Dytiscus proper 321 Stomis 301 Colymbetes 323 Catascopus 301 Hygrobia 324 Colpodes 301 Hydroporus 324 Pericalus 301 Noterus 325 Mormolyce 302 Haliplus 325 Sphodrus 302 Gyrinus BllACHELYTRA 325 Ctenipus Calathus 303 303 327 Taphria 303 Staphylinus 327 Patellimani 303 Fissilabra 328 Dolichus 304 Oxyporus 329 Platynus 304 Astrapaeus 329 Agonum 304 Staphylinus proper 329 Anchomenus 305 Xantholinus 330 Callistus 305 Pinophilus 330 Oodes 305 Lathrobium 330 Chlxnius 305 Longipalpi 331 Epomis 306 Psederus 331 Dinodes 306 Procirrus 331 Lissauchenus 306 Stilicus 331 Rembus 306 Evsesthetus 331. Dicslus 307 Stenus 332. XIV SYSTEMATIC INDEX. Denticrura 332 Oxytelus 332 Osorius 332 Zyropliorus 3S3 Prognatlia 3o'3 Coprophilus 333 Depressa 333 Omalium 333 Lesteva 333 Micropeplus 334 Proteinus 334 Aleochara 334 Microcephala 334 Lomechusa O i^ £■ Tacliinus 335 Tacliyporus 335 SERRICORNES 336 SECTION I. Stehnoxi 337 THIBZ I. BrPIlESTIDES oo7 Buprestis 338 Ihiprestis proper 338 Truchys 339 Aphanisticus 340 Melasis 340 TRIBE II. Elatehides 340 Elater 340 Galba 342 Eucnemis 342 Adelocera 342 Lissomus 342 Chelonarium 343 Throscus 343 Cerophytum 344 Cryptostoma 344 Nematodes 344 Hcmirhipus 345 Ctenicera 345 Elater proper 345 Campylus 346 Phyllocerus 346 SECTION II. Maiacodehmi 347 tribe I. Cebhionites 347 Cebrio 347 Physodactylus 348 Cebrio proper 348 Anelastes 349 Callirhips 349 Sandalus 349 llhipicera 350 Ptilodactyla 350 Dascillus 350 Elodes 350 Scyrtes 351 Nycteus 351 Eubria 351 TRIBE II. Lamptribes 351 Lampyris 352 Lycus 352 Dictyoptera 352 Omalisus 353 Amydetcs 354 Plieng-odes 355 Lampyris proper 355 Drilus 356 Cochkodonus 356 Telephorus 357 Silis 358 INIalthinus 358 TRIBE III. Melxribes 358 Melyris 359 Malachius 359 Dasytes 360 Zyg-ia 360 •Melyris 360 Pelocophorus 361 Diglobicerus 361 tribe IV. Clerii 361 Clerus 361 Cylidrus 361 Tillus 262 Priocera 362 Axina 362 Eurypus 362 Thanasimus 363 Opilo 363 Clerus proper 363 Necrobia 364 Enoplium 364 tribe v. Ptiniores 364 Ptinus 365 Ptinus proper 365 Gibbium 366 Ptilinus 366 Xyletinus 367 Dorcatoma 367 Anobium 367 SECTION III. tribe I. Xylotrogi 368 Lymexylon 368 Atractocerus 368 Hylecsetus 369 Lymexylon proper 369 Cupes 369 Rhysodes 370 CLAVICORNES 370 section I. TBIBE I. Palpatores 371 Mastigus 371 Mastigus 371 Scydmsenus 371 SYSTEMATIC INDEX. XV TRIBE II. HiSTEROIDES 372 Hister 373 Hololepta 373 Hister proper 374 Platysoma 374 Dendrophilus 374 Abrxus 374 Onthophilus 374 TRIBE III. SiLPHALES S75 Silpha 375 Sphaerites 375 Necrophorus 376 Necrodes 377 Silpha proper 378 Thanatophilus 578 Oiceptoma 379 Phosphuga 379 NecrophUus 379 Argyrtes 380 TRIBE IV. SCAPHIDITES 380 Scaphidium 380 Scaphidium proper 380 Choleva 381 TRIBE v. NlTIDtTLARI^ 381 Nitidula 381 Colobicus 382 Thymalus 382 Ips 382 Nitidula proper 383 Cercus 383 Byturus 383 TRIBE VI. Engidites 383 Dacne 384 Dacne proper 384 Cryptophagus 384 TRIBE VII. Dehmestini 385 Dermestes 385 Aspidiphorus 385 Dermestes proper 385 Megatoma 386 Limnichus 386 Attagenus 387 Trogoderraa 387 Anthrenus 387 Globicornis 387 TRIBE VIII. BXRRHII 388 Byrrhus 388 Nosodendron 388 Byrrhus proper 388 , Trinodes 389 SECTION II. TRIBE I. ACANTHOPODA 390 Heterocerus 390 TRIBE II. Macrodactyla 390 Dryops 391 Potamophilus 391 Dryops proper 39I Elmis 392 Macronychus 392 Georissus 392 PALPICORNES 392 TRIBE I. Hydhophilii 393 Hydrophilus 393 Elophorus 394 Hydrpchus 394 Ochthebius 394 Hydraena 393 Spercheus 394 Globaria 395 Hydrophilus proper 396 Limnebius 397 Hydrobius 397 Berosus 397 TRIBE II. Sph^ribiota 398 Sphseridium 39S Cercydion 398 LAMELLICOllNES 399 TRIBE I. Scarabjeides 401 Scarabaeus 40 1 Coprophagi 402 Ateuchus 403 Pachysoma 404 Gymnopleurus 404 Sisyphus 405 Circelliura 405 Coprobius 405 Chseridium 405 Hyhoma 405 Eurysternus 405 Oniticellus 406 Onthophagus - 406 Onitis 407 Phanaeus 407 Copris 407 Aphodius 408 Psammodius 408 E up aria 408 Arenicoli - 409 ^gialia 409 Chiron 409 Lethrus 410 Geotrupes 41 1 Ochodscus 412 Athyreus 412 Elephastomus 412 Bolbocerus 413 Hybosorus 413 Acanthocerus 414 Trox 414 Phoberus 414 XVI SYSTEMATIC INDEX. Cryptodus 414 Sinodendron 438 Msechidius 414 iEsalus 438 Xylophili Oryctes Agacephala Orphnus Scarabaeus proper Phileurus 415 413 416 416 4ir 417 Lamprima Ryssonotus Pholidotus Lucanus proper Ceruchus Platycerus 438 439 439 439 440 440 Hexodon 418 Nigidius 440 Cyclocephala Chrysophora Kutela 418 419 419 MgllS Figulus Syndesus 440 440 440 Macraspjs 419 Passalus 441 Chasmodia 419 Paxillus 441 Ometis 420 Heteromera. Phyllophagi 420 MELASOMA 442 Pachypus 421 Pimelia 444 Amblyteres 421 Plmeila proper 445 Anoplognathus 432 Trachyderma 446 Leucothyreus 422 Cryplucheile 446 Apogonia 422 Erodius 446 Geniates 422 Zophosis 446 Melolontha proper 423 | Nyctelia 447 Rhisotrogus 425 Hegeter 447 AmpJiimalla 425 Tentyria 447 Ceraspis 425 Akis 448 Arcodes 426 Elenophorus 448 Dasypus 426 Eurychora 449 S erica 426 Adelostoma 449 Diphucephala 426 Tagenia 450 Macrodactylus •- , 42r Psammetichus 450 Plectris 427 Scaurus 450 Popilia 427 Scotobius 450 Euchlora 427 Sepidium 450 Mimela 427 Trachynotus 451 Anisoplia 427 Moluris 451 Lepisia 427 Blaps 452 Dicrania 428 Oxura 453 Hoplla 428 Acanthomcra 453 Monocheles 428 Misolampus 453 Anthobii 429 Blaps proper 453 Glaphyrus 429 Gonopus 454 Amphicoma 430 Heteroscelis 454 Anthipna 430 Machla 455 Chasmopterus 430 Scotinus 455 Chasme 431 Asida 455 Dicheles 431 Pedinus 456 Lepitrix 451 Opatrinus 456 Pachycneraus 431 Dendarus 456 Anisonyx 431 Heliophilus 456 Melitophili 432 Eurynotus 456 Trichius 433 Isocerus 456 Platygenia 434 Pedinus, Dej. 457 Cremastocheilus 434 Blaptinus 357 Goliath 435 Platyscelis 457 Inca 435 Tenebrio 458 Cetonia 435 Cryptichus 458 Gymnetis 436 Opatrum 458 Macronota 435 Corticus 459 TRIBE II. Orthocerus 459 LtlCAiriDES 437 Chiroscelis 459 Lucanus 437 Toxium 459 SYSTEMATIC INDEX. Toxicum Boros Calcar Upis Tenebrio proper Heterotarsus TAXICOKNES THIBE I. DiAPEKIAlES Diaperis Phaleria Diaperis proper Neomida Hypophlaeus Trachyscelis Leiodes Tetratoma Eledona Coxelus TRIBE II. COSSYPHENES Cossyphus Cossyphus proper Helaeus Nilio STENELYTRA TRIBE I. Helopii Helops Epitragus Cnodalon Campsia Spheniscus Camaria Acanthopus Amarygmus Sphaerotus Adelium Helops proper Lacna Stenotrafchelus Strongylium Pytho PeJmatopus or ra- ther Scotodes tribe II. CiSTELIDES Cistela Lystronichus Cistela proper Mycetochares Allecula tribe iii. Serrgpalpides Dircaea Orchesia Eustrophus Hallomenus Dircaea proper Melandrya H3'pulus Serropalpus Vol. III.~(3) 459 460 460 46s 460 461 461 462 462 463 463 463 464 464 464 464 465 465 465 465 466 466 466 466 468 468 469 469 469 469 469 470 470 470 470 471 471 471 472 472 472 472 472 473 473 473 474 474 474 474 475 475 475 475 476 476 Conopalpus TRIBE IV. CEdebierites CEdemera Nothus Calopus Sparedrus Dytillus (Edemera proper TRIBE T. RHTSrCHOSTOMA Mycterus Stenostoma Mycterus proper Rhinosimus TRACHELIDES TRIBE I. J^ABRIARI.1; Lagria Lagria proper Statyra Hemipephis TRIBE II. PiROCHROIDES Pyrochroa Dendroides Pyrochroa TRIBE III. MoRDEIlOIfJE Mordella Ripiphorus Myodites Pelocotoma Mordella proper Anaspis Ctenopus TRIBE IV. AlfTHICIDES Notoxus Scraptia Steropes Notoxus proper TRIBE V. HORIAIES Horia Horia proper Cissites TRIBE VI. nANTHARIDI.aB Meloe Cerocoma Hycleus Mylabris Lydus CEnas Meloe proper Tetraonyx Cantharis Zonitis Nomognathus Gnathium XVll 476 477 477 477 478 478 478 478 478 479 479 479 480 480 480 481 481 481 481 482 482 482 482 482 483 483 484 484 484 485 485 485 485 485 486 486 486 487 487 487 487 487 488 489 489 489 490 491 492 492 493 493 493 XVIU SYSTEMATIC INDEX. Sitaris 493 Onycteims 493 Apalus 493 Tetramera. UHYNCOPHORA 494 Bruchus 496 Anthribus 496 Hhimaria 496 Bruchus proper 496 Rhoebus 497 Xylophilus 49r Attelabus 497 Apoderus 497 Attelabus proper 497 Rhynchites -197 Apion 497 Rhinotia 498 Eurhiiuis 498 Tubicenus 498 Brentus 498 Brentus proper 498 Ulocerus 499 Cylas 499 Brachycerus 499 Curculio 500 Cyclomus 500 Curculio proper 501 Leptosomus 502 Prostomus 502 Leptocenis 502 Cratopus 502 Lepropus 502 Hadromcrus 502 Hyhstmotus 502 OthiorhyncliUb 503 Omias 503 Pachyrhyncluis 503 Psalidium 503 Thylacites 503 Syzygops 503 Hyphantus 503 Myniops 503 Liparus 503 Hypera 503 Hylobius 504 Cleonua 504 Lixus 504 Rhynchaenus 504 Tamnophilus 505 Bagous 505 Brachypus 5C5 Balaninus 505 Rhynchaenus proper 505 Sybines 505 Myorhinus 506 Cionua 506 Orchestes 506 Rhamphus 506 Amerhinus 507 Baridius 507 Camptorhynchus 507 Centrinus 507 Zygops 507 Centrorhynchus 508 Hydaticus 508 Oribitis 508 Cryptorhynchus 508 Tylode 508 Calandra 509 Anchonus 509 Orthochsetes 509 Rliina 509 Calandra proper 509 Cossonus 510 Dryopthorus 510 XYLOPIIAGI 510 Scolytus 511 Hylurgus 511 Hylesinus 511 Scolytus proper 511 Camptocerus 512 Ploiotribus 512 Tomicus 512 Platypus 512 Paussus 513 Paussus proper 513 Cerapterus 513 Bostrichus 514 Bostrichus proper 514 Psoa 514 Cis 514 Nemosoma 514 Monotoma 515 Synchita 515 Cerylon 515 Rhyzophagus 515 Monotoma proper 516 Lyctus 516 Lyctus proper 516 Diodesma 516 Bitoma 516 Mycetophagus 517 Colydium 517 Mycetophagus pro- per 517 Triphyllus 517 Meryx 518 Dasycerus 518 Latridius 518 Silvanus 518 Trogosita 518 Trogosita proper 519 Prostomis 519 Passandra 519 PLATYSOMA 519 Cucujus 520 Cucujus proper 520 Den^'ophagus 520 Uleoiota 520 LONGICORNES 520 TBIBE I. Priomi 522 SYSTEMATIC INDEX. XIX Parandra 523 Spondylis 523 Prionus 524 TRIBE ir. Cerambicini. 525 Cerambyx 526 Lissonotus 526 Megaderus 527 Dorcacerus 527 Trachyderes 527 Lophonocerus 527 Ctenodes 528 Phsenicocerus 528 Callichroma 528 Acanlhoptera 529 Stenocorus 529 Furpuricenus 529 Cerambyx proper 5i0 Hamaticerus 530 Gnoma, Dej. 531 Callidium 532 Certalium 532 Clitus 532 Obrium 533 Rhinotragus 533 Necydalis 533 Stenopterus 533 Necydalis proper 534 Distichocera 534 Tmesisternus 535 Tragocerus 535 Leptocera 535 TRIBE III. Lamiabi^ 536 Acrocinus 536 Lamia 536 Acanthocinus 536 Tapeina 536 Pogonocherus 537 Tetraopes 537 Monochamus 537 Mesosa 537 Lamia proper 537 Dorcadion 538 Parmena 538 Saperda 538 Gnoma, Fab. 538 Adesmus 539 Apomecyna 539 Colobothea 539 Thyrsiu 539 TRIBE IF. ^EPTURETJE 540 Leptura 540 Desmocerus 541 Vesperus 541 Rhagium 542 Rhamnusiuni 542 Toxotus 542 Stenoderus 542 Distenia 542 Cometes 542 Leptura proper 543 EUPODA 543 TRIBE I. Saghides 544 Sagra 545 Megalopus 545 Sagra proper 545 Orsodacna 545 Psammcechus 546 tribe ir. Criocehides 546 Crioceris 546 Doiiacia 546 Hxmonia 547 Ptauristes 547 Crioceris proper 547 Auchenia 548 Megascelis 549 CYCLICA 549 tribe I. Cassidari^ 550 Hispa 551 Alurnus 551 Hispa proper 551 Chalepus 552 Cassida 552 Imatldlum 552 Cassida proper 552 tribe II. CURISOMELIN^: 553 Cryptocephalus 553 Clythra 554 Chlamys 554 Lamprosoma 555 Cryptocephalus proper 555 Choragus 555 Euryope 555 Eiimolpus 556 Chrysomela 556 Colaspis 556 Podontia 556 Phyllochai'is 557 Doryphora 557 Cyrtonus 557 Paropsis 557 Apamxa 557 Timarcha 558 Chrysomela proper 558 Phaedon 559 Prasocuris 559 tribe III. Galerucit.^ 559 Galeruca 560 Adorium 560 Luperus 560 Galeruca proper 560 Altica 560 Odogonotes 561 XX SYSTEMATIC INDEX. CEdionychus Psylliodes Dibolia 561 561 562 Mtica proper Longitarsus CLAVIPALPI 562 562 562 Erotylus Erotylus proper Triplax Languria Phalacrus 563 563 564 564 564 Ag^thidium 564 Trimera. FUNGICOLJE 565 Eumorphus 565 Eumorphus proper Dapsa Endomychus 565 566 566 Lycoperdina 566 APHIDIPHAGI 566 Coccinella 567 Lithophilus 567 Coccinella proper 567 Clypeaster 568 PSELAPHII 568 Pselaphus 569 Chennium 569 Dionix 569 Pselaphus proper 569 Bithynus 570 Areopagus 570 Ctenistes 570 Byraxis 570 Claviger 570 Claviger proper 570 Articerus 570 THIRD GREAT DIVISION OF THE ANIMAL KINGDOM. CRUSTACEA, ARACHNIDES, AND INSECTA: OR ARTICULATED ANIMALS WITH ARTICULATED FEET(1). These last three (2) classes of the Articulata, which were united by Linnaeus under the general name of Insecta^ are distinguished by at least six(3) articulated feet. Each articu- lation is tubular, and contains the muscles of the succeeding one, which always moves by gynglymus, that is, in but one direction. The first articulation, which attaches the foot to the body, (1) For the sake of brevity, I have desig'nated them by the term Condylopes. This series of articulations, of which their body is composed, has been compared by some Naturahsts to a skeleton, or the vertebral column. But the use of this denomination is so much the more fallacious, in as much as these articulations or pretended vertebrae are mere portions of thickened skin, and as this skin is continu- ous, simply being thinner, and almost membranous at intervals or at the joints. A general character, which serves to distinguish these animals from all other Inverte- brata, consists in their exuviabilUy, or habit of changing their skin. The situation of the encephalon, pharynx, and eyes, as in the more elevated animals, establishes the limits of the back and abdomen, and of their respective appendages. (2) Dr Leach forms a separate class of the Myriapoda. The Arachnides Tra- chearise, considered anatomically, might also constitute another, but they are so closely allied to the Pulmonarise in • so many other particulars, that we have not thought proper to separate them. (3) Hexapoda. Those which have more than six^ are termed by Suvigny the Spiriopoda. I designate them more precisely by the appellation of Hyperhexa- poda, (more than six feet). Vol. Ilf— a 2 CRUSTACEA, ARACHXIDES, INSECTA. and wliich is composed of two pieces(l), is called the coxa, or hip ; the following one which is, usually, nearly in a hori- zontal position, x\\Q femur, or thigh; and the third, generally vertical, the tibia or leg. To these ensues a suite of small ones which touch the ground, forming the true foot, or what is denominated tlie tarsus. The hardness of the calcareous or horny(2) envelope of the greater number of these animals, is owing to that of the ex- cretion, which is interposed between the dermis and epider- mis, or what is termed in man the mucous tissue. This ex- cretion also contains the brilliant and varied colours with which they are so often decorated. They are always furnished with eyes, which are pf two kinds : simple or smooth eyes(3), which resemble a very mi- nute lens, generally three in number, and arranged in a tri- angle on the summit of the head; and compound eyes, where the surface is divided iiito an infinitude of different lenses called facets, to each of which there is a corresponding filament of the optic nerve. These two kinds may be either united or separated, according to the genera. Whether their functions be essentially different in those cases where they are found to exist simultaneously, is a problem that remains to be solved ; but vision is effected in both of them by means differing widely from those which produce it in the eye of the Vertebrata(4). (1) In many of the Crustacea the second portion of the coxa seems to form part of the thighs. The tibia, as in the Arachnides, is divided into two joints. (2) According to M. Aug. Odier, 3Iem. de la Soc. d'Hist. Nat, 1823, t. I, p. 29 et seq., the substance of this envelope is of a peculiar nature, which he calls Chi- tine. He states that the phosphate of lime forms the great mass of all the salts contained in the teguments of Insects, while that in the shell of the Crustacea is but trifling, though it abounds in the carbonate, which is not found in the prece- ding animals. Other observations, those of M. Straus in particular, demonstrate that the teguments here replace the skin of the Vertebrata, or that they do not form a true skeleton. Those of M. Odier also militate against all the analogies attempted upon this subject. (3) Ocelli stemmata. (4) See the Memoir of Marcel de Serres on the simple and compound eyes of Insects, Montpdlier, 1815, 8vo. Also the observations of M. de Blainville on the eyes of the Crustacea, Bullet, de la Soc. Philomatique. We shall return to this subject at another period. CRUSTACEA, ARACHNIDES, IXSECTA. 3 Other organs which for the first time are here presented to us, and which are found in two of these classes, the Crustacea and the Insecta(l), the antcnnse^ arc articulated filaments; va- rying greatly in form, and frequently according to the sex, attached to the head, appearing to be peculiarly devoted to a delicate sense of touch, and perhaps to some other kind of sen- sation of which we have no idea, but which may refer to the state of the atmosphere. These animals enjoy the sense of smell and that of hearing. Some authors place the seat of the first in the antenn8e(2), others, M. Dumeril for instance, in the orifices of the tracheae, and Marcel de Serres, &c. in the palpi ; neither of these opinions, however, are corroborated by positive and conclu- sive facts. As to the second, it is only in the Crustacea Beca- poda and some few of the Orthoptera, that we can find a visi- ble ear. The mouth of these animals presents a great analogy, which, according to Savigny(3), and at least with respect to the Hex- apoda, extends to those which can only feed by the suction of liquid aliment. * Those called Tritores or Grinders [broyeurs], on account of their having jaws fitted for triturating their food, always present them in lateral pairs, placed one before the other; the anterior pair are especially called mandibles; the pieces which (1) And even in the Arachnides, but under different forms, and witli different functions. (2) As regards insects, and when they are claviform, or terminate in a club more or less developed, or furnished with numerous hairs. According to M. Robineau Desvoidy, the intermediate antennae of tlie Crustacea Decapoda are the olfactory organ. Bullet, des Sc. Nat.,- but he adduces no one direct experiment in proof of his opinion. It would, if this were so, seem probable that in the liighly carnivorous Crustacea, such as the Gecarcini and others, we should find this organ in a comparatively greater state of development, whereas the fact is directly the reverse. His ideas respecting the external composition of the Crustacea Decapoda suppose the existence of a skeleton. He should have commenced, however, by establishing the connexion of these animals with the Fishes, and not by admitting, as a positive fact, what is at least a matter of doubt. (3) Memoire sur les animaux sans vertebres. The original idea was thrown out, but undeveloped, in my Hist. Gen. des Tnsectes. 4 CUUSTACEA, AHACHNIDES, IXSECTA. cover them before and behind are named labia{l), and the front one, in particular, labrum. The palpi are articulated filaments attached to the jaws or to the lower lip, and appear to be employed by the animal in recognizing its food. The form of these various organs determines the nature of the re- gimen with as much precision as the teeth of quadrupeds. The ligula, or tongue, commonly adheres to the lower lip(2). Sometimes, in the Apes and other Hymenopterous insects, it is considerably elongated, as -are also the jaws, forming a sort of false proboscis {profniiscis) at the base of which is the pharynx, and frequently covered by a sort of sub-labrum, styled by M. Savigny the epipharynx{3). At other times, __ ^ . — (1) We here more particularly allude to Insects with six feet, or to the Ilcxa- poda. (2) Or rather labium, since the other is termed labrum. It is protected, before, by a horny production formed by a cutaneous prolongation, and articulated at tlie base with an inferior portion of the head called the mentura or chin. Its palpi, ahva3's two in number, are distinguished from those of the maxill^e by the epithet labial. When the latter amount to four they are designated as external and inter- nal; they *e considered as a modification of the external and terminal division of the maxillae. This production, wdiich, in his Ulonates or the Orthoptera, Fabricius termed the Galea, is still the same maxillary division, but more dilated, arched, and fitted to cover the internal division which, here, on account of its scaly consistence and of its teeth, resembles a mandible. In the' last insects, and particularly in the Libellulae, the interior of the buccal cavity presents a soft or vesicular body, dis- tinct from the lip, and which, compared to the Crustacea, appears to be the true tongue — labium, Fab. This part is perhaps represented by those lateral divi- sions of the ligula termed paraglossa;. (See the Coleoptera Cai-nivora, Hydro- phili, Staphylini, the two pencil-shaped pieces that terminate the lip of the Lucani, Apiariae, &c.) The above mentioned Insects, the Orthoptera and the Libellulae of Linnxusj evidently demonstrate that this membranous and terminal portion of the inferior lip, which projects more or less between its palpi, and is particularly elon- gated in several of the Hymenoptera, is very distinct from that internal caruncle which I consider the tongue properly so called; notwithstanding this, nearly all Entomologists designate this external extremity of the lip by the name of ligula, or languette. To say, however, that the tongue properly so called, is usually so intimately connected with the lip that at the first glance they seem to be con- founded, is correct. The pharynx is situated in the middle of tlie anterior face of this lip a little above its root, and in the Coleoptera provided with paraglossx, at their point of union. In order to understand well the primitive composition of the under lip, it must be studied in the larva;, and chiefly in those of the Aquatic Carnivorous Coleoptera. See General Observations on Insects. (3) There is a membranous production beneath the labrum, in many Coleop- CRUSTACEA, ARACHNIDES, INSECTA. 5 in the Honiptera mn\ Diptcra, the mandibles and maxilltr are replaced by scaly pieces in the form of setcE, which arc re- ceived in an elongated tubular sheath, that is either cylin- di'ical and articulated, or formed with more or less of an elbow, and terminated by a kind of lips. In this case they constitute a true proboscis. In others that also live by suction, the Xe- pidoptera, the maxillae alone aregreatly elongated and 'united, producing a tubular setiform body,. resembling a long, slen- der, and spiral tongue (or the spirifrompe^ Lat.): the re- maining parts of the mouth are considerably reduced. Some- times again, as in many of the Crustacea, the anterior feet approach the maxillos, assume their form, and exercise part of their functions — the latter are then said to be multiplied. It may even happen that the true maxilhc become so much re- duced, that the maxillary feet supply their place in toto. Whatever be the modifications of these parts, however, they can always be recognized and referred to a general type(l). tera, which appears to me to be analogous to tlie ep'ipharynx. The labrum is to it, what the mentum is to the labium. (1) It is only by a compiu-ative and gradual study of the mouth of the Crus- tacea, that we can acquire correct and cxdfct ideas rc'specting the various trans- formations of these parts, and the means of establishing-, if not a certain, at least a probable general concordance between these vai'ious org-ans in tlie three classes. The mandibles, maxilla;, and the labium, are in fact, a sort effect appro- priated to the masticatory or buccal functions, hut susceptible of being- so modified as to become org.ans of locomotion. This principle even extends to tlie antcn- n'x, or at least to the two intermediate ones of the Crustacea, ny adopting it, we are enabled to reduce the composition of these organs to one general type, and we shall hereafter see that, in this respect, neither the Arachnides nor Myriapoda present any anomaly. CLASS I. CRUSTACEA. Tlie Crustacea are articulated animals, with articulated feet, respiring by means of branchiie, protected in some by the bor- ders of a shell, and external in others, but which are not in- closed in special cavities of the body, and which receive air from openings in the surface of the skin. Their circulation is double, and analogous to that of the Mollusca. The blood is transmitted "from the hear-t, which is placed on the back, to the different parts of the body, whence it is sent to the bran- chiJE, and thence back again to the heart(l). These branchiaB, sometimes situated at the base of the feet, or even on them, and at others on the inferior appendages of the abdomen, either form pyramids composed of laminae in piles, or bristled with setae or tufted filaments of simple ones, and even appear in some cases to consist wholly of hairs. Some of the Zootomists, Baron Cuvier in particular, had already made known to us the nervous system of various Crus- tacea of diiferent orders. The same subject has lately been thoroughly examined by Messrs Victor Audouin and Milne Edwards in their third Memoir on the Anatomy and Physio- logy of these animals — Ann. des Sc. Nat. XIV, 77, — and all that is now w^anting to complete their researches, is the pub- lication of those made by M. Straus on the Branchiopo'da and the Limuli in particular, which they have not noticed. (1) See the order Decapoda. CRUSTACEA. 7 *^The nervous system of the Crustacea submitted to our observation, say they, presents itself in two very different as- pects, which constitute the two extremes of the modifications visible in that class. Sometimes, as in the Talitrus, this ap- paratus is constituted by numerous similar nervous inflations, arranged in pairs, and united by cords of communication in such a way as to form two ganglionic chains, separated from each other and extending throughout the length of the animal. At others, on the contrary, it is solely composed of two gan- glions or knotty enlargements, dissimilar in form, volume, and arrangement, but always simple and azygous, and situated, one in the head and the other in the thorax. Such is the case in the Maia. ''^ These two modes of organization, at the first glance, cer- tainly seem essentially diiferent, and if the study of the ner- vous system of the Crustacea were limited to these two ani- mals, it would be extremely difficult to recognize the analogy between the central nervous mass in the thortix of the Maia, and the two ganglionic chains which occupy the same region of the body in the Talitrus. But if we remember the various facts detailed in this memoir, we necessarily arrive at this re- markable result.'' They were led to it by the exact and careful study of the nervous system of various intermediate Crustacea, forming so many links of the series, such as the CymothoiB(l ), the Phyllo- somce(2), Astacus(3), Palcemon and Palinurus. They have also supported their positions by the observations of Cuvier and those of M. Treviranus. The consequence deduced by them is, that notwithstanding this difference, the nervous system of the Crustacea is formed of the same elements, which, insulated in some and uniformly distributed throughout the length of the body, present in others, various degrees of centralization, at first from without inwardly, and then in a longitudinal di- ll) Isopoda. (2) Stomapoda. (3) For this subgenus and the two following subgenera see the Decapoda Macroura. 8 CRUSTACEA. rection; and that finally, this approximation in all directions is carried to its extreme point, when it is reduced to a single nucleus in the thorax — as in Cancer properly so called, or the Brachyura. Of all the Decapoda Macroura examined by Messrs Audouin and Edwards, the Palinurus was found to have the venous system most centralized ; and in fact, that animal in our system is l)ut little removed from the Brachyura. But this should not be the case with Palaemon and the Asta- cini, for according to them the former approximates more closely in this respect to Palinurus than the latter, while in our arrangement the second precede the first, a disposition which appears to us to be founded on several very natural characters. The Crustacea are apterous or deprived of wings, furnished with compound eyes, though rarely with simple ones, and usually with four antennse. They have mostly — the Paecilo- poda excepted — three pairs of jaws, the two superior ones, designated by the name of mandibles, included ; as many foot- jaws(l), the last four of which, however, in a great many in- stances, become true feet ; and ten feet properly so called, all terminated by a single small nail. When the last two pairs of foot-jaws exercise the same functions, the number of feet is in- creased to fourteen. The mouth, as in insects, presents a labrum and a ligula, but no lower lip properly so called, or comparable to that of the latter ; the third pair of foot-jaws, or the first, closes the mouth externally, and replaces that part. The sexual organs, at least those of the males, are always double, and situated on the breast or at the inferior origin of that posterior and abdominal portioji of the body commonly (1) Auxiliary jaws, as th^ are termed by M. Savigny, at least when speaking- of the Crustacea Decapoda. As the two superior ones, in the Amphipoda and Isopoda, form a sort oflip, he there calls them the auxiliary lip. He distinguishes the jaws in Phalangium, a genus of Arachnides, as principal jaws,- those which are attached to the palpi— /a/se palpi, according to him; and as supernumerary javjs, those which are attached to the first four feet. Those parts of the same animals which havel)een considered as mandibles, are his rnandibules succe'danes. He ad- mits of two auxiliary lips in the Scolopendrae. CRUSTACEA. 9 called the tail, and never posteriorly. Their envelope is usually solid, and more or less calcareous. They change their skin several times, and generally preserve their primitive form and natural activity. They are mostly carnivorous and aquatic, and live several years. They do not attain their adult state until after casting their skin a certain number of times. With the exception of a few in which these changes somewhat in- fluence their primitive form and modify or augment their locomotive organs, they are at birth, size apart, such as they are always to remain. Division of the Crustacea into Orders. The situation and form of the branchisB, the mode in which the head is articulated with the trunk(l), the mobility or fix- edness of the eyes(2), the organs of manducation, and the tegu- ments, constitute the basis of our divisions, and give rise to the following orders(3). We divide this class into two sections, the Malacostraca, and the Entomostraca(4). The first are usually furnished with very solid teguments, of a calcareous nature, and with ten or fourteen feet(5), gene- rally unguiculated. The mouth, situated in the ordinary (1) with respect to this term, and that of thorax, which are frequently em- ployed in an arbitrary manner, see ourg-eneral observations on the class of Insects. (2) These organs are either pediculated and movable, or sessile and fixed. It Is from this character that Lamarck has divided the Crustacea into two great sec- tions, the Pediocles and the Sessiliocles; for which denominations, but restricting its application to the Malacostraca, Doctor Lead) has substituted those of Podop- thalma and Edriopthalma. Gronovius was the first who had recourse to this dis- tinction. (3) Although we possess but few observations on the nervous system of the Crustacea, all those which have been made support the truth of our divisions. (4) They might be still further divided into the Dentata and the Edentata, ac- cording to the presence or absence of the mandibles. Jurine, Jun., has already proposed these divisions in his excellent Memoire sur I'Argule foliace. (o) The four antei-ior, when there are fourteen, are formed by the last four pos- terior foot-jaws. In tlie Decapoda, the six foot-jav. s belong to the mouth, and per- form the office of maxill?E. Vol. in.— B 10 CRUSTACEA. place, is composed of a labrum, tongue, two mandibles (fre- quently furnished with palpi), and two pairs of maxillae co- vered by the foot-jaws. In a great number each eye is placed on an articulated and movable pedicle, and the branchiae are concealed under the lateral margins of the upper or lower shell ; in the others they are usually placed under the post- abdomen. This section consists of five orders : the Dec apod a, Stomapoda, L^modipoda, Amphipoda, and the Isopoda. TJie four first embrace the genus Cancer of Linnaeus, and the last his Oniscus. The second, the Entomostraca, or " Insects with shells" of Muller, is formed of the genus Monoculus, Lin. Here the teguments are horny and very thin, while a shell, resem- bling a buckler, composed of from one to two pieces, covers or incloses the body of the greater number. The eyes are almost always sessile, and frequently there is but one. The feet, the number of which varies, are mostly fitted for nata- tion, and without a terminal nail. Some of them, having an anterior mouth composed of a labrum, two mandibles — rarely furnished with palpi, a tongue, and one, or at most two pairs of jaws, of which the external ones are naked or are not co- vered by the foot-jaws, approximate to the preceding Crusta- cea. In the other Entomostraca, which seem to approach the Arachnides in several particulars, the organs of manducation are sometimes simply formed by the coxae of the feet, pro- jecting and arranged like lobes bristling with small spines round a large central pharynx. At others they either com- pose a little siphon or beak, used for suction, as in several Arachnides and Insects, or they are wholly (or nearly so) in- visible externally, either because the siphon is internal, or be- cause the suction is produced in the manner of a cup. The Entomostraca are thus dentated or edentated. The first will form our order of the Branchiopoda(I), and the (1) In my work entitled Families Nat. du Regne Animal, the Entomostraca are divided into four orders; the Lophtropoda, Phyllopoda, Xipiiosura, and the Si- PHONOSTOMA. CRUSTACEA. 11 second that of the P^cilopoda, which in the first edition of this work were a mere section of the preceding order. The singular fossils called Trilobites, of which M. Brong- niart has given an excellent Monograph, being considered by him, as well as by many other naturalists, as Crustacea al- lied to the Entomostraca, we will briefly speak of them after we have done with the latter. iZ CRUSTACEA. FIRST GENERAL DIVISION. MALACOSTRACA. The Malacostraca naturally divide themselves into those whose eyes are placed on a movahle pedicle, and those in which they are sessile and fixed. a. Eyes placed on a movable and articulated pedicle. Eyes(l) placed on a movable pedicle composed of two arti- culations, and received into fossulse, distinguish the Decapoda and Stomapoda from all tlie others. Anatomically considered, they appear to be still further removed from them, — Legons d'Anat. Compar., Cuv.; Ann. des Sc. Nat., t. XI, — inasmuch as they are the only ones that present sinuses in which the venous blood is collected previous to its transmission to the branchice on its return to the heart. The Decapoda and Stomapoda resemble each other in se- veral characters common to both. A large plate called a shell covers a greater or less extent of the anterior portion of their body. They all have four antennse(2), the middle ones of (1) Behind the cornea, according to Blainville, is a choroides perforated with numerous holes; thenatrue crystaUine, resting on a nervous ganglion, and divided into a multitude of little fasciculi. (2) We must distinguish the peduncle — s^/pes,— and the stem— caulis, funiculus. The peduncle is thicker, cylindrical, and composed of three joints, a number which seems pecuhar to these organs in their imperfect or rudimentary state. The stem is setaceous, and divided into a variable number of very small joints. That of the external antennae is simple, but that of the interior ones consists of at least two filaments, and in several of the Decapoda Macroura, of three. Passing gi-adually from these latter to the Brachyura, the antennae become shortened, so that, in several of the Quadrilatera, the lateral ones, at least, are very small. In this case the two terminal divisions of the intermediate ones form a sort of bifurcated forceps, or unequal and articulated fingers. MALACOSTRACA. 13 which are terminated by two or three filaments; two mandi- bles, each of which, at its base, bears a palpus that is divided into three joints and usually laid on it, a bilobate tongue; two pairs of jaws ; six foot-jaws, the four posterior of which, in some, are transformed into claws ; and ten feet, or fourteen, in those where the four foot-jaws have that form. In the greater number the branchisBj of which there are seven pairs, are concealed under the lateral margin of the shell : the two anterior pairs are situated at the origin of the four last foot -jaws, and the others at that of the feet properly so called. In the other Crustacea they are annexed, in the shape of tufts, to five pairs of paddles (feet) placed under the post-abdomen. The under part of this posterior portion of the body is similarly furnished, in the others, with four or five pairs of bifid appendages. ORDER I. DECAPODA. The head, in the Decapoda, is closely joined to the thorax, and covered with it by a shell, entirely continuous, but that most frequently exhibits deep lines dividing it into various regions which indicate the places occupied by the principal internal organs(l). The mode of their circulation presents characters which distinguish them from the other Crustacea. (1) M. Desmarest, in his Histoire Naturelle des Crustac^s Fossiles, and in his Considerations Gcn^rales sur la Classe des Crustaces, has presented us, in relation to this point, with an ingenious nomenclature, based on the concordance of the portions of the external surface of the shell with the organs they cover. But, in addition to the fact that the shell of several Decapoda presents no impressions, or has them nearly obliterated, these denominations may be replaced by others more simple, more familiar, and relating to these same organs; as the middle or centre, the anterior and posterior extremities, the sides, &c.: it appears useless to increase our nomenclature in this case. 14 CRUSTACEA. The circumscribed heart(l), of an oval form and with muscu- lar parietes, gives origin to six trunks of vessels, three of which are anterior, two inferior, and the sixth posterior. Of the three anterior arteries, the median — the ophthalmic — is distributed almost exclusively to the eyes ; the two others — the antennaries — spread over the shell, the muscles of the sto- mach, a portion of the viscera and the antennae ; the two in- ferior ones — the hepatics — transmit blood to the liver; the last — the sternal — is the most voluminous of the three, and arises from the posterior part of the body, sometimes on the right side and at others on the left; its chief course is to the abdomen, and to the organs of locomotion. It gives origin to a great number of large vessels, among which we should par- ticularly observe the one called by M. Audouin and Edwards the superior ahdominal, because it arises from the posterior part of that artery, at a short distance before the articulation of the thorax with the abdomen, vulgarly termed the tail, and because it soon dips into the abdomen — tail^ — where it divides into two large branches, running backwards, becoming gra- dually smaller and terminating at the anus. The blood which has nourished these various organs, and thus become venous, collects from all quarters in two large sinuses(2), one on each (1) These observations are extracted from the excellent Memoir of Messrs Audouin and Edwards, published in the Ann. d'Hist. Nat., t- XI, 283 — 314, and 352 — 393. See also the Mem. duMus. d'Hist. Nat., where M. Geoffrot Saint-Ilil- aire has inserted the results of his curious researches on the solids, and on the cir- culation of the Lobster. (2) These learned naturalists compare them to the two lateral hearts of the Ce- phalopoda, and the analogy has been admitted by Baron Cuvier in his g-eneral lie- port on the transactions of the Acad. Roy. des Sc, for 1827; but the idea had been communicated by me to M. Audouin, and was a necessary consequence of my theory of the circulation of the blood in the Crustacea, pubhshfid in a note of my Esquisse d'une Distribution Generak du Regne Animal, p. 5. As the writers alluded to have taken no notice of what I have stated in this particular, both in the pam- phlet quoted, and in my work on the " Famihes of the Animal Kingdom," I beg leave to produce that note. " I submit the following opinion to the judgment of Zootomists, and of M. Cuvier in particular, viz. that in those of the Vertebrata possessed of a circulation, the organ called heart represents, in its functions, a left ventricle, the arterial and dorsal trunk of Fishes and of the larvse of the Ba- trachians; that one or two arteries, which in the Cephalopoda have the form of DECAPODA. 15 side and above the feet, and formed of venous sacs united in a longitudinal series, or like a chain. It is thrown into an external vessel — efferent — of the branchiae, where it is re- newed and becomes arterial ; thence proceeds into an internal vessel — afferent \ and finally seeks the heart through canals — branchio- cardiac — laid beneath the arch of the flanks. All the canals of a side unite in one large trunk, and open into the lateral and corresponding part of the heart by a single orifice, the folds of which form a double valve that opens to allow the transit of the blood from the branchiae to this visciis, but pre- vents a retrograde motion by closing. Examined internally, the heart exhibits numerous fasciculi and muscular fibres, va- riously intercrossed and forming several small chambers before the orifices of the arteries. These chambers are so many small auricles, which communicate freely with each other when it dilates, but appear to form a similar number of little cells for each vessel when it contracts, their capacity being proportioned to the quantity of blood in their peculiar vessels. These vessels debouche in the interior of the heart by eight openings, the two lateral valvular ones above mentioned in- cluded. Such, with the exception of some modifications(l), is the general system of the circulation in the Decapoda. The superior face of the brain(2) is divided into four lobes, each of the two middle ones furnishing from its anterior mar- gin an optic nerve that plunges directly into the pedicle of the eye and there divides into numerous filaments, each of which is destined to a facet in the cornea of that organ. hearts, replace the right ventricle. The focus of the circulation, highly concen- trated in the first of the Vertebrata, thus becomes gradually weaker, so that finally there is no circulation whatever. The dorsal vessel of Insects would then be the mere rudiment of the heart of the MoUusca and Crustacea." I will add, that twenty-five years ago, in my Hist. Nat. des Crust, et des Insedes, I rectified the error of Roesel respecting the nervous cord of the spinal marrow, which had been taken for a vessel. (1) See general observations on the family of the Macroura. (2) These observations are extracted from the Legons d'Anatomie Compar^e of Ilaron Cuvier. For other details and particular facts see the Memoir of Messrs Audouin and M. Edwards, loc. cit. 16 CRUSTACEA. The inferior face of the brain produces four nerves, which belong to the antennae, and that also give off some twigs to the neighbouring parts. Two nervous and very long cords, em- bracing the esophagus laterally and uniting beneath it, arise from its posterior margin. There, as in the Brachyura, this union only takes place in the middle of the thorax, the me- dulla then assuming the form of a ring whose proportions are eight times larger than those of the brain : six nerves on each side arise from this ring : the anterior ones belong to the parts of the mouth, and the five others to the five feet of the same side. From the posterior margin arises another nerve which runs to the tail, without producing any sensible ganglion, and that apparently represents the ordinary nervous cord. Here, as in the Macroura, each of the two nervous cords, previous to uniting beneath the esophagus, and at about the middle of its length, gives off a thick nerve for the use of the mandibles and their muscles. United, they form a first — sub-cervical — ganglion that distributes nerves to the maxillae and the foot- jaws(l); they afterwards continue approximated throughout their length, presenting eleven successive ganglions, each of the five first furnishing nerves to as many pairs of feet, and the remaining six those of the tail; that of the Pagurus has some ganglions less, thus appearing to form the passage from the Brachyura to the Macroura. M. Serres thinks that he has recognized in these Decapoda, vestiges of the great sym- pathetic(2). The lateral margin of the shell is bent under, to cover and protect the branchiae, leaving an opening anteriorly for the (1) According to M. Straus, the anlerior division of the body of the Limuli, that which is covered by a semi-lunar buckler, presents, besides the brain, no other ganglion but this, whence we may infer that the inferior organs of locomo- tion correspond to the parts of the mouth in the Decapoda, Stomapoda, and even in the Arachnides, and that those of the other division of the body, or of the second buckler, are analogous to the feet of the same Decapoda. (2) Messrs Audouin and Edwards have observed in the Maia and in the Palinu- rus a nerve analogous to the one called by Lyonet, in his Jinatomie de la Chenille du Saule, "recurrent." The discovery of the other gastric nerves is also due to them. DECAl'ODA. 17 passage of water. Sometimesj — see Dorippe — the posterior and inferior extremity of the thorax has two peculiar aper- tures for that purpose. The branchiae are situated at the origin of the last four foot-jaws and feet; the four anterior ones have less extent. The six foot-jaws are all of a different form, are applied to the mouth, and divided into two branches, the exterior of which resembles a small antenna, formed of a pe- dicle, and a setaceous and pluri-articulate stem — it has been compared to a whip, palpus flagelUformis{\). The two an- terior feet, and sometimes the two or four following ones, are in the form of claws. The penultimate joint is dilated, com- pressed, and in the form of a liand ; its inferior extremity is lengthened into a conical point, representing a sort of finger, opposed to another formed by the last joint, or the tarsus proper. This one(2) is movable, and has received the name of thumb — pollex ; the other is fixed, and considered as the index — index. These two fingers are also called mordaces. The last is sometimes very short, and has the form of a sim- ple tooth ; in this case the other is bent underneath. The hand with the fingers constitutes our forceps properly so called. The preceding, or antepenultimate joint is termed carpus. The respective proportions and the direction of the organs of locomotion are such, that these animals can walk sideways or backwards. With the exception of the rectum, which opens at the end of the tail(3), all the viscera are contained in the thorax, so that this portion of the body represents the thorax and the greater part of the abdomen of insects. The stomach, sup- (1) There is a long, tendinous and hairy lamina at its base. (2) The hand being placed on its edge, the finger is uppermost. (3) This suite of segments which, in the Crustacea of the first orders, imme- diately succeed those to which the five last pairs of feet are attached, compose what I have termed the post-abdomen. The appellation of tail usually affixed to it, and which, in order to accommodate ourselves to common parlance, we have retained, is very improper; it can only apply to the posterior terminal appendages of the body which extend considerably beyond it. See my Fam. Nat. du Regne Anim., p. 255, et seq. Vol. III.— C 18 CKUSTACEA. ported by a cartilaginous skeleton, is armed internally with five bony and notched appendages, which completes the tri- turation of the aliment. In it, in the moulting season, which arrives near the end of spring, we observe two calcareous bo- dies, round on one side and flat on the other, commonly called crabs'^ eyes, that disappear after the change is completed, thereby inducing us to believe that they furnish the material for the renewal of the shell. The liver consists of two large clusters of blind vessels, filled with a bilious humour, which they pour into the intestine, near the pylorus. The alimen- tary canal is sliort and straiglit. The flanks present a range of holes situated immediately at the insertion of the branchisB, but which can only be seen by removing those organs. . The under shell, viewed internally, at least in several large spe- cies, exhibits transverse cells formed by crustaceous laminae, and separated in their middle by a longitudinal range of the same nature. The sexual organs of the male are situated near the origin of the two posterior feet. Two articulated pieces, of a solid consistence, and resembling horns, stylets, or setaceous an- tennae, placed at the junction of the tail with the thorax and replacing the first pair of subcaudal appendages, are regarded as the male organs of copulation, or at least as their sheaths. But, according to our observations on various Decapoda, each of them consists of a little membranous body, sometimes seta- ceous, and at others filiform or cylindrical, that projects from a hole situated at the articulation of the hip of the two poste- rior feet, with the lower shell. The two vuIvsb are placed on this piece, between those of the third pair, or on their first joint, a disposition depending on the widening and narrowing of the lower shell. Copulation takes place, ventre a ventre, These animals grow but slowly, and live a long time. It is among them that we find the largest and most useful species, but their flesh is not easily digested. The body of some Pali- nuri attains the length of a metre. Their claws are efficacious weapons, and have such power in large individuals, that they have been seen to seize a Goat, and drag it from the shore. DECAPODA. 19 They usually inhabit water, but do not instantly perish when deprived of it; some species ev^en pass a part of their lives on land, only visiting the water in the nuptial season, and for the purpose of depositing their spawn. Even they are compelled to fix their domicil either in buwows, or in cool, damp places. The Decapoda are voracious and carnivorous. Certain spe- cies even penetrate into cemeteries, and devour the dead. Their limbs are regenerated with surprising promptitude, but it is requisite that the fracture be at the junction of the arti- culations, and when accident determines it otherwise, they know how to apply a remedy. When they wish to change their skin, they seek a retired and solitary spot, in order to be sheltered from their enemies, and to remain at rest. When the change is effected, their body is soft, and has a iuore ex- quisite flavour. A chemical analysis of the old shell proves it to be formed of the carbonate and phosphate of lime, united in different proportions with gelatine. On these proportions depends the solidity of the shell : it is much less thick and flexi- ble in the latter genera of this order, and further on, it becomes almost membranous. M. de Blainville has observed that the shell of the Falinurus is composed of four superincumbent lay- ers, the superior and two inferior of which are membranous j the calcareous matter is interposed between them, forming the fourth. Exposed to heat, the epidermis becomes of a more or less vivid red, the colouring principle being decomposed by boiling water; other combinations of this principle produce, in some species, a very agreeable mixture of colours, that fre- quently border on blue or green. The greater number of fossil Crustacea hitherto discovered belongs to the order of the Decapoda. Among those of Eu- rope, the oldest approach to species now living in the vicinity of the tropics; the others, or more modern ones, are closely allied with the living species of Europe. The fossil Crustacea of the tropical regions, however, appear to me to bear the closest similitude to several of those now found there in a liv- ing state, a fact of much interest to the geologist, should the study of the fossil shells of those countries, collected from the deepest strata, furnish a similar result. 20 CRUSTACEA, FAMILY 1(1). BRACHYURA.— Kleistagnatha, Fab. Tail shorter than the trunk, without appendages or fins at the extremity, and doubled under, in a state of rest, when it is received in a fossula on the chest. Triangular in the males, and only furnished at base with four or two appendages, in the form of horns, the superior of which are the largest, it becomes widened, and convex in the females(2), presenting beneath four pairs of double hairy filaments(3), destined to support the ova, and analogous to the sub-caudal natatory feet of the Macroura, and others. The vulvai are two holes situated under the pectus, between the third pair of feet. The antennae are small : each of the intermediate ones, usually lodged in a fossula under the ante- rior edge of tlie shell, terminates in two very short filaments. The ocular pedicles are generally longer than those of the Decapoda Macroura. The auricular tube is almost always stony. The first pair of feet terminate in a forceps or claw. The branchiae are disposed on a single range, in the form of pyrami- dal ligulsB, composed of a multitude of leaflets piled one on another, in a direction parallel to their axis. The foot-jaws are generally shorter and broader than in the other Decapoda, the (1) The sections thus named are based on an ensemble of important anatomical characters, and generally correspond to the Linnxan genera, and sometimes also to those established by Fabricius in his earlier works. These families are more extensive than the sections thus named in my other writings: but if they be con- sidered as first divisions of orders, and if what I have termed tribes be considered as famihes, it will be seen that the method is essentially the same. There is, then, the opinions of others to the contrary notwithstanding, no real discrepance in this respect. On the same principle, the subgenera, with the exception of some whose characters are too minute or too slightly marked, will become genera in a more detailed and special system. (2) The apparent number of segments, which is usually seven, sometimes also varies according to the sex; it is less in the females. Dr Leach has made great use of this consideration, which appears to us of but little importance, and opposed to the natural order. (3) Several of these filaments exist in the males, but in a rudimental state. DECAPODA. 21 two external ones forming a sort of lip(l). Their nervous system also differs from that of the Macroura(2). This family, as in several of the systems anterior to the distribution of these animals by Daldorf, might constitute but one genus, that of Cancer, Lin. In the greater number, all the feet are attached to the sides of the ])ectus, and are always exposed; this is the case in the first five sec- tions. The first, or that of the Pinnipedes(3), to this character, adds that of having the last feet, at least, terrainated by a very flat or fin- like joint that is oval or orbicular and broader than the same joint of the preceding feet, even when they also are shaped like a fin. They seldom frequent the coast, and are generally found in the high (1) Those of the Macroura are longer and narrower. It is on this difference that Fabricius established his order of the Exochnata. (2) See general observations on the Decapoda. (3) This systematic arrangement of the Brachyura is artificial, or but little natural in some respects; in consequence of which, we have somewhat altered it in our Families Naturelles du 'Regne Animal. The Quadrilatera compose our first tribe, at the head of which are the Ocypodaa,nd other Land-Crabs, ending with the River-Crabs, or the Telphusx. The Ahcuata form the second. That of the Crxptopoda appearing to us more closely allied to the preceding one than the Triakgularia, will immediately follow, and be the tlilrd, and not the fourth, as in this method. Immediately after the Arcuata we will place those genera whose claws are in the form of a crest, whose lateral antennx are always very short, and the third articulation of whose foot-jaws is triangular, and frequently entire, or without any emargination; such are the Hepati, Matutse, OvUhyise, and Mursix. Brachyura approaching the latter in the form of the same articulation, but whose claws differ, and where the lateral antennae are salient, advanced, and fre- quently hairy, such as the Thise, Pirimelse, and AtdecycU, will immediately pre- cede these latter svibgenera. • As the Telphusx seem to be connected with the Eriphije and the I'ilumni, and as from these we naturally pass to Cancer properly so called, or the Cancer, Fab., it follows that the Portuni and other natatory Ar- cuata should be at the head of this tribe. Then follow the Orbicciaria, the Triangularia, and the Notopoda. But of these the JDromiw and the Dorippes should be placed higher in the scale. The Homobe, Lithodes, and Raninae, appear tome to be of all the Brachyura, those which are most closely allied to the Mac- roura. The external foot-jaws of the Homolse and of the Lithodes greatly resem- ble those of the Macroura by their length and projection. Although we have divided the Decapoda into two genera only, in order to con- form to modern systems, and to diminish the number of subgenera, our sections may be converted into tribes, corresponding to as many subgenera, to be after- wards divided into various subgeneric sections. 22 CRUSTACEA. seas. With the exception of the Orithyise, we observe but five dis- tinctly marked segments in the tail of the males, while that of the females presents seven. We Avill begin with those in which all the feet, except the claws, are natatory. Matuta, Fabr. The Matutse have an almost orbicular shell armed on each side with a very stout looth in the form of a spine; the superior edge of the hands dentated like a crest, and their external face studded with pointed tuberclcsj the third joint of the external foot-jaws, without any apparent emargination, terminates in a point, so that it forms, with the preceding joint, an elongated and almost right- angled triangle. The external antennce arc very small, and the ocular pedicles slightly arcuated. De Geer mentions a species — Cancer lalipes, which he says is from the American seas, and has its front terminated by a straight and entire margin. All those we have seen, how- ever(l), were brought from the East-, and the middle of that margin always presents a bidenlated or emarginated projection. The PoLYBius, Leach, Is allied to the Portuni, but the shell is proportionably narrower and more rounded; the sides are merely furnished with ordinary teeth. The third joint of the external foot-jaws is obtuse and emar- ginated. The eyes are much thicker than their pedicles, and glo- bular. But a single species is as yet knawn(2); it was found on the coast of Devonshire, and has also been observed by M. D'Or- bigny on the sea-coast of the western departments of France(3). In all the following swimmers, the two posterior feet only are formed like fins(4). We may first separate those whose shellis almost ovoid and trans- (1) M. victor, Fab.; Herbst, VI, U.—3I. planipes, Fab.; Herbst., xlviii, 6; M. lunaris. Leach, Zool. Miscell., cxxvii, 3—5, vai:;—!!. Peronii, lb., tab., ead., 1 — 2. Perhaps we should refer the fossil species called by M. Desmarest, Por^wne d'Hericart, Hist. Nat. des Crust., Foss. V, 5, to this genus, or the Mursia, Leach. (2) Polyhius Hensloioii, Leach, Mai ac. llrit., IX, B. (3) The tarsi of the intermediate feet of the Portumni, Leach, are almost com- pressed into a fin; they might be placed after the Polybii. (4) Always wider and more oval than the preceding tarsi. DEOAPODA. 23 versely truncated before, and where the tail of the males (the only- sex known) consists of seven distinct segments. Such is the Orythyia, Fabr. The only species known, — Orith. mamillaris, Fabr., Cancer bimaculatus, Herbst., XVIII, 101, is found in the sea of China, or at least forms a part of the collections of Insects sold by its inhabitants to foreigners. The ocular pedicles are longer in proportion than those of the Portuni. The shell of the last swimmers is rj^uch wider before than behind, forming either the segment of a circle narrowed towards the tail and truncated, or a trapezium, or is almost in the shape of a heart. Its greatest transverse diameter generally surpasses the opposite one. There are but five segments in the tail of the males, instead of the seven found in that of the females, the number usually pecu- liar to the tail of the Decapodaj the third and the two following ones are confounded or form but onej frequently, however, traces of them are discovered, at least on the sides. We will first separate those whose eyes are supported by very long and slender pedicles, arising from the middle of the anterior margin of the shell, extending to its lateral angles, and received into a groove run under the edge. Such is the PoDOPHTHALMus, Lam., Where the shell forms a transverse trapezium, wider and straight before with a long spiniform tooth behind the ocular cavities. The claws are elongated, spiny, and similar to those of most of the spe- cies of the genus Lupa, Leach. The only living species known(l) inhabits the coasts of the Isle of France and those of the neighbouring seas. The valuable cabinet of one of the mast learned fossil con- chylidogists of Europe, contains an internal cast of a fossil Po- dophthalmus, to which M. Desmarest has afiixed the name of its possessor, M. de France(2). The ocular pedicles of the other Crustacea, belonging to this sec- tion, are short, occupy but a very small portion of the transverse diameter of the shell, are placed in oval cavities, and resemble, generally, those of the ordinary Crabs with which these swimmers (1) Podophthalmus spinosus, Latr., Gener. Crust, et Insect., I, 1, and II, 1; Leach, Zool., Miscell. cxlviii; Portunus vigil. Fab. (2) Hist. Nat. des Crust. Foss., V, 6, 7, 8. 24 CRUSTACEA. are almost insensibly connected. They may all be united in one single subgenus, that of PoRTUNUs, Fab. Certain species(l) peculiar to the Indian Ocean, such as the Ad- mete, Herbst., LVII, 1, are distinguished from all the following ones by their shell, which is of a transversely quadrilateral form, narrowed posteriorly, and whose ocular cavities occupy its anterior lateral angles; the eyes are thus separated by an interval almost equal to the greatest width of the shell. The insertion of the lateral antennas is at a considerable distance from these cavities. Other species, whose shell forms the segment of a circle, poste- riorly truncated and widest in the middle, are remarkable for the length of their claws, which is at least double that of the shell. Each side presents nine teeth, the posterior largest and spiniform. The tail of the males is frequently very different from that of the females. These Portuni constitute the genus Lupa, Leach, and are mostly of a large size and foreign to Europe. One species, however, is found in the Mediterranean(2). A third division will consist of species analogous to the last in the form of their shell, but whose lateral teeth, usually five in num- ber, are nearly equal, or where, at least, the posterior tooth differs but slightly from the preceding onesj the length of the claws does not much exceed that of the shell. Those which have from six to nine teeth on each side are exotic. The Portunus tranquebaricus, Fabr., Herbst, Cane, XXXVIII, 3, is the only one known that has nine equal teeth on each lateral edge; it is large, and is much esteemed as food. We suspect the P. leiicodonte, Desmar., Hist. Nat. des Crust. Foss., VI, 1 — 3, is the same species in a fossil state; it is also from India. The following species, all from European seas(3), have five teeth on each lateral edge of the shell. (1) Genus THAtAMiTA, Lat. (2) Portunus Dufourii, Latr., Nouv. Diet. d'Hist. Nat., Ed. II. This species, figured in the Diet. Class. d'Hist. Nat., closely approaches the Cancer hustatus, Lin., which he says is found in the Adriatic. The following are to be referred to the same division: Cancer pelagicus, Herbst., Iviii, 55, — C. forceps. Id., Iv, 4; Leach, Zool. Miscell., liv; — C. sanguinokntus, Herbst., VIII, 56, 57; — C. cedonulU, Id., xxxix; — C. reticulatus, lb., 1; — Chastatus, lb., Iv, 1; — C. menestho, lb., 3; — C. ponticus, lb. 5. (3) For the Mediterranean species see Petagna, Rissoand Ollvi; for those on the western coast of France and the British seas, the Catalogue Methodiquc des Cms- IJECAPODA. 25 P. puber, Fab.,: Cancer puber, L.; Penii. Brit. Zool.,IV,iv, 8j Herbst., VII, 59; Leach, Malac. Brit., VI. Covered with a yellowish down; eight small teeth between the eyes, the two middle ones longest, obtuse and divergent; claws sulcated, armed with a stout dentated tooth on the inner side of the carpus, and from one joint to the following one or the hand; fingers blackish. This species is usually called in France, where its flesh is considered a delicacy, rEtrille. P. corrugatus; Cancer corrugatits, Penn. Brit. Zool., IV, pi. V, 9; Leach, Malac. Brit., VII, 1, 2. The shell rugose, covered with a yellowish down, and furnished with three equal, and almost lobuliform teeth in front; the three posterior teeth of the lateral margins very sharp and spiniform. P. moanas} Cancer mcenas, L., and Fab. This common spe- cies of the French coast, called Crabe enrage, appears to me to belong to the Portuni, rather than to the Crabs properly so calk:d; its posterior fins are only somewhat narrower. Such was the first opinion of Dr Leach, who subsequently made a peculiar genus for it called Carcinus, (Malac. Brit., XII, tab. v). It also has five teeth on each side, and a similar number in front, the internal oculars included. The top of the shell is glabrous, finely shagreened, with deeply impressed lines. The tarsi are striate; the upper edge of the hand is so compressed as to form a rounded ridge, terminated by a small tooth; a second but stronger one is observed on the inner side of the preceding joint; fingers striate, and almost equally dentated, with a black- ish tip. A fossil species is found in the marly limestone of Monte- Bolca, which, according to Desmarest, — Hist. Nat. des Crust. Foss., p. 125, is closely related to the mocnas. In the Portiinus Rondeletii, Risso, there are no teeth in front. The one he calls longipes, presents the same character, but its feet are longer in proportion than those of other analogous spe- cies. We will form a fourth division with the subgenus. Platyonichus, Lat. Which name has replaced that of Portumnus, Leach, on account tac^s du departement du Calvados," by l?rebisson, and especially the excellent work of Dr Leach, Malacostraca Fodophfkalmia Britanniac. M. Desmarest has well de- veloped the system of this author in his Considerations Generales sur les Crustac^s, an extremely useful book to those who make this branch of Zoologj' their study. See also our article Fortune, Encyc Methodique. Vol. IIL— D 26 CRUSTACEA. of the too great similarity between the latter and the word Portunus already adopted. Here the shell is at least as long as it is broad and almost cordate. All the tarsi of the feet, the claws excepted, terminate in a small, semi-elliptical, elongated and pointed lamina j the index is strongly compressed. This division also comprises but a single species, the Cancer latipes, Plancus, — De Conchis minus notis III, 7, B, C, — and which has also been figured by Leach — Malac. Brit., IV. There are three teeth front, and on each lateral edge five(l). From the swimmers we pass to those whose feet all terminate in a point, or conical and sometimes compressed tarsus, but never form- ing a fin properly so called. Those of them whose shell is tapering, forming the arc of a circle before, and narrowed and truncated be- hind, in which the claws of both sexes are alike, where the number of the caudal segments is the same as in the Portuni, and which, with the exception of the tarsi, almost completely resemble them, will constitute our second section, that of the Arcuata. In the Cancer, P'abr. Or the Crab properly so called, the third joint of the external foot-jaws is emarginated or marked with a sinus near the internal and almost square extremity. The antennae scarcely extending be- yond the front and composed of but few articulations, are flexed and glabrous, or but slightly hairy. The hands are rounded and have no appearance of a crest on the upper edge. The radical joint of the external antennae is, in some, much larger than the following ones, and resembles a lamina; terminated by a sa- lient and advanced tooth, closing inferiorly the internal corner of the ocular cavities. The fossulie of the middle or internal antennae are nearly longitudinal. Such is the C. pagiiriis, L.; Crabe poupart, &c.; Herbst., IX, 59. Shell reddish, wide, plane, almost smooth above, with nine festoons in each lateral margin, and three teeth in front. Its claws are large, smooth, with black fingers studded internally with blunt tubercles. It is sometimes a foot wide, and weighs five pounds. Common on the Atlantic coast of France, but less abundant in the Mediterranean. Its flesh is esteemed. Dr. Leach separates it generically from the other Crabs: Malac. Brit., XVII, x. In the others, the lower joints of the Antennae are cylindrical; al- though somewhat larger, the first does not diff'er from the following (1) See the article Plaiyonique, Eiicyc. Methodique. DECAPODA. 27 ones in form or proportion, and does not extend beyond the internal canthus of the ocular fossuloe; those of the intermediate antennse are prolonged in a direction rather parallel to the breadth of the shell than to its length. There are some of them — C. W-dentatus, Fab., in which the ex- tremity of the fingers are excavated like the bowl of a spoon: they form the Clorodius, Leach. Several species, where they terminate in a point, are remarkable for the arcuation of the edges of the shell which terminate posteriorly by a fold and overlapping projection, in the manner of an angle. Those with a tridentated front, and whose shell only presents that projection or posterior tooth, com- pose his genus Carpilius. The species of this subdivision, — C. co- rallmus, F. j C. mauculatus, Id., are marked with round blood- coloured spots. They more particularly inhabit the Indian Ocean. Many fossil Crabs appear to me to belong to this subdivision. The Xaniho, of the same, some of which, Xanth. Jioridus, Leach, Malac. Brit., XI; — Cancer poressa, Oliv., Zool. Adriat., II, 3, inhabit the coast of France, have their antennae inserted in the internal can- thus of the ocular fossulge, and not in the outer one, as in those just mentioned. Other considerations v/ould authorise us to augment the number of these divisions, but our limits require us merely to indicate the principal ones. The " Crabe vulgaire de nos cvtes" of the first edition of this work, has in this one been placed among the Portuni. — P. mxnas. PiRiMELA, Leach. These Crustacea completely resemble Crabs, but their external antennse extend considerably beyond the front, and their stem, longer than their pedicle, consists of numerous joints. The fossulse of the intermediaries, as in the C. pogurus, are rather longitudinal than transversal. But a single species is known, the P. denticidata, Leach, Malac. Brit., VIII; it is found in the British channel and in the Mediterranean. Perhaps we should refer to this species, the fossil described by Desmarest under the name of Jltelecycle ru- glieitx, in the Hist, Nat. de Crust. Foss., IX, 9. Atelecyclus, Leach(l). Fossulae of the intermediate antennae longitudinal; lateral antennae (1) We had, at first, placed this subgenus, as well as tire following one, among the Orbicularia. 26 CRUSTACEA, elongated, salient and composed of many joints, but very hairy as well as the claws; the latter strong, and with compressed hands. The third joint of the foot-jaws sensibly narrowed above, resembling an obtuse or rounded tooth; conical tarsi, and the ocular pedicles of the ordinary size. The tail is longer than in the preceding Crus- tacea. Two species have been described(l). One from the coast of England, of a sub-orbicular form, and the other from that of France, Mediterranean as well as Oceanic. The Thia, Leach, Approaches Atelecyclus in the lateral antennae, in the direction of the fossulse in which the intermediaries are placed, in the form of the third joint of the external foot-jaws, and in the sub-orbicular shell; but the eyes, together with the pedicles, are extremely small and scarcely salient. The tarsi are strongly compressed and sub- elliptical. The front is arcuated, rounded, and without any marked dentations. The pectoral space between the feet is very narrow, and of the same breadth throughout. The claws are much weaker in proportion. The shell is smooth, and in some respects the Thiae approach the Leucosiee and the Corysies. The type(2) of this subgenus, whose habitat was unknown, has been discovered by Milne Edwards in the sandy shores of the Mediterranean, near Naples. Risso — Journ. de Phys., 1822, p. 251, — described a second, dedicated to M. de Blainville, which he found in the river at Nice. The MuRSiA, Leach(3), Of which but a single species is known, and which is peculiar to that part of the Ocean which bounds the southern extremity of Afri- ca, approaches the Matutae and several Portuni, in the long spine with which each side of the shell is armed posteriorly; it also approximates to the true Crabs in the form of the shell and of the external foot-jaws, with this difference, that their third joint forms an elongated square, narrowed and obliquely truncated at its supe- rior extremity; but, as in the Calappae and Hepati, the hands are strongly compressed above, having a sharp and dentated edge, re- sembling a crest(4). (1) See Consid. Gener, sur laClasse des Crust, Desmar., p. 88, 89. (2) Thiapolita, Leach, Zool. Miscell. ciii. (3) This name must be changed to avoid confounding the division with that of Nursia, anotlier subgenus. (4) Desmarest, Consid. Gener., &.c., IX, 3- DECAPODA. 29 Hepatus, Latr. The Hepati have a considerable affinity with the true Crabs in the widened form of their shell, and the shortness of their lateral anten- nae, approaching the Mursise and Calappse in their compressed hands, the upper edge of which resembles a crest; but the third joint of their external foot-jaws forms an elongated, narrow, and pointed triangle, without any apparent emargination, a character also ob- served in the Matutae and Leucosiae. The species(l) which served as the type of this division was confounded by Fabricius with the Calapp. It is as large as an ordinary Pagarus. The shell is yellowish, dotted with red, and the margins finely and unequally crenulated. The eyes are small and approximated, and the feet are traversed by red bands. Although the tail of the male has but five complete seg- ments, the traces of two others may still be discovered on the sides. This species is common at the Antilles. In our third section or that of the Quadrilatera, the shell is nearly square or heart-shaped, the front generally prolonged, in- flected or much inclined, and forming a sort of clypeus. There are seven segments, distinctly marked across their whole breadth, in the tail of both sexes. The antennae are usually very short. The eyes of most of them are fixed on long or stout pedicles. Several live habitually on land, inhabiting holes excavated by them- selves; others frequent fresh water streams. They move with great swiftness(2). A first division will comprise those in which the fourth joint of the external foot-jaws is inserted at the superior internal extremity of the preceding one, either in a short, truncated projection, or in a sinus of the inner margin. They approach nearest to the Crabs proper. The shell of some is nearly square, or a trapezium, but not trans- verse, or almost in the form of a truncated heart. The ocular pedi- cles are short, and inserted either near the lateral and anterior an- gles of the shell, or more internally, but always at a considerable distance from the middle of the front. Here comes the (1) Hepatus fasciatus, Latr. ; Desmar., Consider., IX, 2; — Calappa angustata, Fabr. ; Cancer princeps, Bosc; Herbst., xxxvii, 2. See also his Cancer armadillus, VI, 42, 43. (2) I consider them, with respect to their habits and some of the characters of their organization, as being the furthest removed from the other Decapoda; they should be placed at one of the extremities of that order. 30 CRUSTACEA. Eriphia, Lat. Where the lateral antennae are inserted between the ocular cavi- ties and the median antennae: the nearly cordiform shell is truncated posteriorly, and the eyes are removed from its anterior angles. The coast of France furnishes a species — Cancer spinifrons, Fab.; Herbst., XI, 65; Desmar., Consider., XIV, 1, which is the Pagicrus of Aldrovandus. The sides of its shell are fur- nished with five teeth, the second and third bifid. The front and claws are spiny; the fingers black. Trapezia, Lat. The TrapezicC resemble the Eriphise in the insertion of their late- ral antennse, but their shell is nearly square, depressed, and smooth; the eyes are placed at its anterior angles, and the claws, in compa- rison with the other feet, very large. All the species are cxotic(l), and inhabit Eastern Seas. The PiLUMNus, Leach, Differs from the two preceding subgenera, in the insertion of the lateral antenna; at the internal extremity of the ocular cavities, above the origin of the pedicles of the eyes. The Pilumni, as to the form of the shell, approach nearer to the Crustacea of the second section, than the other Quadrilatera, atid in this respect stand some- what ambiguously between the two. As in most of the Arcuata the third joint of their foot-jaw is nearly square or pentagonal. The lateral antennae are longer than the ocular pedicles, and have a seta- ceous stem longer than the peduncle and composed of numerous small joints. The tarsi are simply pilose(2). Thelphusa, Lat.(3) The lateral antennae situated as in the Pilumni, but shorter than the ocular pedicles, composed of but few joints, and with a cylin- drico-conical stem hardly longer than its peduncle. The shell is (1) Cancer cymodoce, Herbst., li, 5;~C. rufo-pundaius. Id., xlvii, 6;—C. glaber- rimus. Id., xx, 115. See the article Trap^zie, Encyc. Methodique. (2) Seethe article Pj7«??ine, Encyc. Method., and Desmarest, op.cit. p. 111. (3) The Potamophiles of the first edition of this work. That name having- been already apphed to a genus of Coleopterous Insects, I have substituted the present one.— See this word in the second edition of the Nouv. Diet. d'Hist. Nat. They are the Potamobise, Leach, Potamon, Savigny. DECAPODA. 31 almost shaped like a truncated heart, and the tarsi are furnished with spinous or dentated ridges. Several species are known, all of which inhabit fresh water, but capable, as it would appear, of living at a distance from it for a considerable time. One of them, mentioned by the an- cients, is found in the south of Europe, the Levant, and in Egyptj it is the Crabe Jluviatile, of Belon, Rondelet, and Ges- ner(l). It is very common in several brooks and various lakes of the craters of the south of Italy; its effigy is observable on different antique Grecian medals, particularly on those of Si- cily. The shell is about two inches in each diameter. It is greyish or yellowish, as the animal is living or dead, mostly smooth, with little incised rugse and asperities on the anterior sides. The front is transversal, inclined, reflected, and eden- tated. The claws are rough, with a reddish spot at the extrem- ity of the fingers, which are long, conical, and unequally den- tated. The Greek monks eat it raw, and during lent it forms one of the articles of diet used by the Italians. Two naturalists, travellers of the government, prematurely taken from the sciences, Delande and Leschenault-de-Latour, discover- ed two other species; one was collected by the first in his travels to the south of Africa, and the other by the second in the mountains of Ceylon. The Cancer senex o{ Fabricius (Herbst., XL, 5), should, in my opinion, be referred to the same subgenus. It inhabits the East Indies. A species peculiar to America, the Thelphusa serrata, Herbst., X, ii, is proportionably wider and flatter than the others, pre- senting certain characters which seem to indicate a particular division(2). Other Quadrilatera having, like the preceding ones, the fourth joint of the external foot-jaws inserted in the internal extremity of the previous joint, differ from them in the trapezoidal, transverse and (1) See Olivier Voy., en Egypte, pi. xxx, 2; and the plates of Nat. Hist, in the great work on that country. (2) See also the subgenus Octpode. I have made a new one called Thicho- DACTTLUs, with a fresh-water species from lirazil analogous to the preceding ones, but with an almost square shell, the third joint of the external foot-jaws forming an elongated triangle hooked at the end, and the tarsi covered with a close down. The Graspus tesselatus, of the pi. (cccv, 2) of Nat. Hist., Encyc Method., is also the type of the new genus Meiia, but one of too little importance to be treated of in detail in a work like this. 32 CRUSTACEA. widened form of the fore-part of the shell, as well as in their ocular pedicles, which, like those of the Podophthalmi, are long and slen- der extending to the anterior angles, and inserted near the middle of the front. The claws of the males are long and cylindrical: such is the GoNOPLAX, Leach. Two species of which are found in European seas; one of them, however, may possibly be a mere variety of the other. The first — Cancer angulatiis, L.; Herbst., I, 13; Leach, Ma- lac. Brit., XIII, has the anterior angles of its shell prolonged into a point, and a second, but smaller spine behind. Two others are observed on the claws of the males, one on the joint called the aria, and the other on the internal side of the carpusj the hands are elongated, and somewhat narrowed at base; ano- ther tooth is found on the superior extremity of the thighs of the other feet. The body is reddish. It inhabits the western coast of France, and that of England. In the second — Cancer rhomboides, L., the shell presents no other spines than those formed by the prolongation of the ante- rior angles. The body is smaller, and of a reddish-white or flesh colour. From the rocky localities of the Mediterranean(l). In the second division of the Quadrilatera, the fourth joint of the external foot jaws, or those which cover the other parts of the mouth below, is inserted in the middle of the extremity of the preceding joint, or more outwardly. Sometimes the shell is trapezoidal or ovoid, or is shaped like a heart truncated posteriorly. The ocular pedicles, inserted at a short distance from the middle of its anterior margin, extend to its ante- rior angles, or even beyond them. Commencing with those whose shell is transversely quadrilateral, widened before and narrowed behind, or which has the form of an egg, we first observe the Macrophthalmus, Lat. Where the shell, as in the Gonoplaces, is trapezoidal and the claws are long and narrow; the ocular pedicles are slender, elongated, and lodged in a groove under the anterior margin of the shell. The first joint of the intermediate antennae is rather transverse than lon- gitudinal, and the two which terminate them are very distinct and (1) See the article Rhombille, Encyc. Methodiquc DECAPODA. 33 of a mean size. The external foot-jaws are approximated inferiorly at their inner edge, leaving no interval between them, and their third joint is transverse. They(l) inhabit the Eastern Ocean and the seas of New Holland. The following, which constitute the subgenera Gelasimus, Ocypode, and 3Iictyns, inhabit burrows, are remarkable for the celerity of their course, and have the fourth pair of feet, and next to them, the third, longer than the others. The intermediate antennae are excess- ively small and hardly bifid at the extremity^ the radical joint is nearly longitudinal. They are peculiar to hot climates. Here the shell is solid, of a quadrilateral or trapezoidal form, ■widest before. Gelasimus, Lat. — UcUt Leach. Eyes terminating their pedicles like a small headj third joint of the external foot-jaws forming a transverse square; last segment of the tail of the males almost semi-circular, that of the females nearly orbicular. ' The lateral antenniE are longer and slenderer in proportion than those of the Ocypodes. One of the claws, now the right, and then the left, varying in individuals of the same species, is much larger than the other; the fingers of the small one are frequently shaped like a spoon or spatula. The animal closes the entrance of its bur- row, which it excavates in the vicinity of-the sea-shore, or in marshy places, with its large claw. These burrows are cylindrical, oblique, very deep, and placed close to each other, but are usually inhabited by a single individual. Their habit of holding the large claw in an upright position before the body, as if making an appellative gesture, has obtained for them the name of Calling-Crabs — Cancer vocans. One species, observed by Bosc in South-Carolina, passes the three winter months in its retreat without leaving it, and only visits the sea when about to spawn(2). (1) Gonoplax transversus,'L2Xv., Encyc. Method., Hist. Nat, ccxcvii, 2; — Can- cer hrevis, Herbst., Ix, 4. The Gowo/j/ace f?e Zci/rejY/e, a fossil species described by Desmaresl, Hist. Nat. des Crust. Foss., IX, 1 — 4, and perhaps also his G. incise, IX, 5, 6, may be a Macrophthalmus; generally speaking-, however, his fossil Gonoplaces are Gelasimi. The species he calls Gelasime luisante, VIII, 7, 8, does not appear to differ from the living one which I have called the maracoani, Encyc. Method., lb., ccxcvi, 1. (2) See the article Gelasime, Nouv. Diet. d'Hist. Nat., Ed. IT, and the same article in the work of Desmarest on animals of that class. The Crabs, cietie-ete, detie-panama, of Marcgrave, appear to me synonymous with the Gelasimus pugi- lutor. According to tlie observations of M. Marion, communicated to the Acad, Vol, ni.— E 34 CRUSTACEA. OcYPODE, Fabr. Eyes extending into the greater part of the length of their pedicles, or claviformj third joint of the external foot-jaws forming a long square,' tail of the males very narrow, and the last joint an elongated trianglej that of the females is oval. The claws are nearly similar, strong, but short, and the forceps shaped like a reversed heart. Agreeably to the indication afforded by their generic name, these Crustacea run with great swiftness, which indeed is such, that a horse can scarcely overtake them, whence the name of Eques, given to them by the older naturalists. They are now sometimes termed Land-Crabs, and occasionally, na- turalists have confounded them with the Gecarcini, under the gene- ral denomination of Tourloxiroux. The Ocypodes, during the day, remain in the holes or burrows they have excavated in the sand, near the sea-shore, and quit them after sun-set. Ocyph. eqiies; Cancer cursor, L. ; Cancer eques, Bel.; Ocyph. ippeus, Oliv., Voy. dans I'Emp. Ottom., II, xxx, 1. Distin- guished from all the others by the bundle of hairs, which termi- nate the ocular pedicles. It inhabits the coast of Syria, that of Africa bordering on the Mediterranean, and is even found at Cape de Verd. In the Ocyp. cerathojihthalmus; Cancer cerathopt., Pall., Spic. Zool., fasc. IX, V, 2 — 8, the superior extremity of these pedicles ex- tends beyond the eyes for more than a third of their whole length, in a conical and simple point. The forceps are codi- form, very rough, and their cutting edge dentated. From the East Indies. In others the pedicles are terminated by the eyes forming a sort of club. Some from the eastern continent and all those of the western world are thus formed, but the latter possess a peculiar cha- racter, which indicates more aquatic habits, or that they swim with more facility: their feet are smoother, flatter, and furnished with a fringe of hairs. Such is the O. blanc, Bosc. Hist. Nat. des Crust., I, 1. The Cumuru of Marcgrave belongs to this division(l). In classing the collection of the Museum d'Histoire Naturelle, we Roy. des Sc, by M. de Blainville, this inequality of the forceps is peculiar to the males, at least such was the case in all the numerous specimens examined by him in his voyage to the East Indies. (1) For the Ocypodes of the western continent, see the observations of M. Say, Journ. Ac. Nat. Sc. Philad. His Ocyp. reticulatus is a Grapsus. Consult, also, the article Ocypode^ Nouv. Diet. d'Hist. Nat., and the work of M. Desma- rest. DECAPODA. 35 placed among the Ocypodes, under the specific name of quadriden- tata, a crustaceous animal, which appears to us to bear a close re- semblance to the Gecarcin trois-epines, Desmar., a fossil species, Hist. Nat. des. Crust. Foss., VIII, 10; he suspects it may belong to ttie genus Thelphusa. Here, at least in the females, the shell is very thin, membranous, and flexible, and the body almost round or subovoid. The ocular pedicles are sensibly shorter than in the preceding subgenera. First comes the MicTYRis, Lat. Where the body is subovoid, highly inflated, narrower and more obtuse before, and truncated posteriorly; the clypeus considerably di- minished, and its extremity narrowed into a point. The claws form an elbow at the junction of the third and fourth joint, the latter of which is almost as large as the hand; the other feet are long, with angular tarsi. To these essential characters we will add, that the ocular pedicles are curved and crowned with globular eyes; that the external foot-jaws are very ample, and their internal edge hairy, the second joint being very large, and the following one almost semi- circular. Two species are known: one is found in the Australasian Ocean(l), and the other in Egypt(2), where it was observed by M. Savigny. Immediately after these come the Pinnotheres, Lat. Very small Crustacea, which during a part of the year, in Novem- ber particularly, inhabit various bivalve shells, chiefly the Mytili and Pinnae. The shell of the females is sub-orbicular, very thin and soft, while that of the males is solid, almost globular and somewhat narrowed into. a point before. The feet are of a middling length and the claws straight and formed as usual. The external foot-jaws present but three distinct joints, the first large, transversal, and arcuated, and the second furnished at its internal base with a small appendage. The tail of the female is very ample and covers the whole under part of the body. The ancients believed that they resided with the Mollusca, in (1) Lat, Gener. Crust, et Insect., I, 40; Encyc, Method., Atlas d'Hist. Nat. ccxcvii, 3; Desmar., Consider., XI, 2. This subgenus, and th&.t oi' Pinnotheres, in the first edition of this work, constituted part of the Orbicularla; but in their nat- (oral order they approach the Ocypodes, Gecarcini, &c. (2) PI. d'Hist. Nat., of the great work on Egypt. 36 CRUSTACEA. whose shells they are found, on friendly terms, warning them of danger and seeking food for them. The inhabitants of certain dis- tricts, at the present day, attribute to their presence the unwhole- some qualities sometimes manifested in the Mytili(l). We now arrive at Crustacea, which, although analogous to those just mentioned in the insertion of their ocular pedicles, are re- moved from them in respect to their shell. It is heart-shaped and truncated posteriorly, elevated, dilated and rounded on the sides near the anterior angles. The ocular pedicles are shorter than those of the preceding subgenera, and do not quite extend to the lateral extremities of the shell. The intermediate antennae are always ter- minated by two very distinct divisions. The inhabitants of the f>onch colonies designate them by various appellations, such as, Tourlouroux, Crabes-pcints^ Crates de terre, and Crabes violets, which may apply to different species, or to varieties from age; no observa- tions worthy of credence have as yet settled this point of nomencla- ture. These animals more particularly inhabit intertropical coun- tries and those which adjoin them. Their habits are a constant source of interest to travellers, but by abstracting from their ac- counts all improbable and doubtful facts, their history will be as follows. The greater portion of their life is passed on land, where they secrete themselves in holes, from which they never issue but at night. Some inhabit cemeteries. Once in the year, about the spawn- ing season, they collect in immense bands and pursue a direct course to the sea, heedless of all obstacles; after depositing their ova, they return much enfeebled. It is said that they seal up the mouth of their burrow during the time they are casting their shell. When this is effected, and while yet soft, they are called Boursiers, and their flesh is much esteemed, although sometimes poisonous. This quality is attributed to the fruit of the manchineel, which they are supposed, falsely perhaps, to have eaten. In some of them, such as the UcA, Lat., The size of the feet, commencing, with those of the second pair, progressively diminishes; they are extremely pilose, and the tarsi simply sulcated without any remarkable spines or dentations. The only species known — Cancer uca, L., Herbst., VI, 38, inhabits the marshes of Guiana and of Brazil. In others, the third and fourth pair of feet are longer than the (1) For species see Leach, Make. Podoph. Britt, and Desmar., Consider. Gen^r. sur les Crust., 116. DECAPODA. 37 second and fifth; the tarsi are marked with dentated or very spinous ridges. They form two subgenera. Cardisoma, Lat. The four antennas and all the joints of dhe. external foot-jaws exposed; the three first joints of these same foot-jaws straight; the third shorter than the second, emarginated superiorly and nearly cordiform; the first of the lateral antennae almost similar and broad. They are called Crabes blancs at the Antilles, though sometimes they have a yellow shell striped with red(l). Gecarcinus, Leach. The four antennae covered by the clypeus; second and third joints of the external foot-jaws, large, flattened, arcuated, and leaving a space between their inner sides, the last one forming a curvilinear trian- gle, obtuse at the summit; it reaches to the clypeus, and covers the three following ones, or the fourth, fifth, and sixth. The most common species — Cancer ruricolciyh.^ Herbst., Ill, 36, when young, IV, xx, 116; xlix, 1, is of a more or less lively blood-red colour, more or less extended, and sometimes spotted with yellow with a deeply marked impression of the letter H. It is the Crabe violet, and Crabe pemt of travellers; the name of Tourlourou appears to me to be more peculiarly applied to this species(2). Sometimes the shell is nearly square, subisometrical or not, broader than it is long, flattened, and the front turned down for nearly the whole of its width. The ocular pedicles are short and inserted at the anterior lateral angles. The two ordinary divisions of the intermediate antennae are very distinct. The inner sides of the exterior foot-jaws are separated, leaving an angular space be- tween them; their third joint is almost as long as it is broad. The (1) Cancer cordatus, L.; — Cancer carnifex, Herbst., XLI, 1, IV, 27; — C. guan- Aumi, Marcgrave. The tarsi have four ridges; there are two additional ones in the Gecarcini. (2) See the article Tourlourou in the Encyc. Methodique. Messrs Audouin and Edwards have lately communicated to the Acad. Roy. des So. , some very curious remarks upon an organ peculiar to these animals, which forms a sort of reservoir capable of containing a certain quantity of water, and placed imme- diately above the branchiae. This accounts for the unusual convexity of the ante- rior sides of their thorax. 38 CRUSTACEA. claws are short and thick, and the other feet very flat; the fourth pair, and tlien the third are longer than the others; tarsi spinous. Plagusia, Lat. The mediate antennse lodged in two longitudinal and oblique fissures traversingthe whole thickness of the middle of the clypeus(l). They are inferior or covered by this part in Grapsus, Lam. Where the shell is somewhat wider before than behind, or at least not narrower, while in the Plagusiae it widens from before back- wards. The Grapsi are found throughout all parts of the globe, but are more particularly abundant in the vicinity of the tropics. They are not seen in Europe beyond 50° of latitude. If I mistake not they are called Ceriques at Martinique. Marcgrave has figured some Brazi- lian species by the names of Aratu, Aratu-pinima (Grapsus cruen- tatus, Lat.) and Carava-una. At Cayenne they are' called Raga- bewnba, or soldier. These animals conceal themselves during the day under stones, &c., at the bottom of the sea. I have been informed that some of them even climb up the trees on its shores and hide beneath their bark. The broad and flattened form of their body and feet enables them to support themselves for a moment on the surface of the water; they always walk sideways, sometimes to the right and at others to the left. Certain species inhabit rivers within the bounds of tide water, but most frequently live on their banks or on land. They assemble in great numbers, and when any one appears among them, they hurry to the water with a tremendous noise, caused by striking one claw against the other. Their habits are similar to those of other carnivorous Crustacea(2). G. varius, Lat.; Cancer marmoratiis, Fab.; Oliv., Zool., Adr., II, 1; Cancre madre, Rondel.; Herbst., XX, 114. Size middling; nearly square, hardly broader than long; yellowish or livid; greatly elongated above, and marked with numerous fine lines and points of a reddish-brown; four flattened projec- (1) P. depressa, Lat. ; Herbst, III, 35; — F. clavimana, Lat., Herbst., lix, 3; Uesmar., Consider., XIV, 2. The tail appears to me to consist of but four dis- tinct segments. The third, however, presents one or two deep and transverse lines. In the Grapsi there are seven segments, the third of which has an angular dilatation on each side of its base. (2) See Bosc, Hist. Nat. des Crust. DECAPODA. 39 tions arranged transversely at the base of the clypeus, and three teeth at the anterior extremity of each lateral edge. The tarsi are spiny. The G. porte-pinceau; Cuv. Regne Anim., IV, xii, 1; Rumph., Mus. X, 2; Desman, Consider., XV, 1, is remarkable for the numerous, long and blackish hairs with which the superior surfaces of the fingers are furnished. The tarsi are without spines, a character exclusively peculiar to this species. It is found in the East Indies(l). In our fourth section or the Orbiculata(2), the shell is either sub-globular, rhomboidal or ovoid, and always very solid; the ocular pedicles are always short or but slightly elongated; the claws of unequal size according to the sex, those of the males being largest; there are never sevfen complete segments in the tail; the buccal cavity grows gradually narrower towards its superior extremity, and the third joint of the external foot-jaws always forms an elon- gated triangle. The posterior feet resemble the preceding ones, and neither of the latter is ever very long. In the CoRYSTEs, Latr., The shell is an ovoidal oblong, and crustaceous;the lateral antennae are long, projecting and ciliated; ocular pedicles of a mean size and separated; third joint of the external foot-jaws longer than the pre- ceding one, with a visible emargination for the insertion of the next. The tail is composed of seven segments, the two middle ones obli- terated in the males. A species — Cancer personntus, Herbst., XII, 71, 72; Leach, Malac. Brit., VI, 1, is known on the coast of France. The lateral edge of its shell is marked with three notches on each •side. A second was brought from the Cape of Good Hope by the late Delalande. Leucosia, Fab. Form of the shell varying, but generally ovoid or almost globular, and always very hard and stony; lateral antennae and eyes very small; eyes approximated. The third joint of the external foot-jaws is smaller than the second, and without any apparent internal sinus; (1) See the article Pfagtme, Encyc. Method., and the Histoire des Animaux sans vertebres of Delamarck, genus Grapse. (2 ) The Orythise and the Dorippes, in a natural series, would, in my opinion, belong to this section, and lead to the Corystes; their shell is a truncated ovoid- 40 CRUSTACEA. these parts are contiguous inferiorly along the internal edge, and form an elongated triangle, the extremity of which is received into two upper cells of the buccal cavity. The tail, which is ample and suborbicular in the females, usually consists of from four to five seg- ments, but never seven. Doctor Leach(l) has separated this genus of Fabricius into seve- ral genera, which, however, we will consider as simple divisions. Those species Avhich have a. transversal shell, with the middle of its sides greatly prolonged or dilated, so as to resemble a cone or cylinder, form his genus Ixa{2). Those which have a rhomboidal shell with seven conical points, resembling spines on each side, compose that of Jphis. If the shell still has the same rhomboidal figure, but merely pre- sents angles or sinuses on the sides, it becomes his genus Nursia. If these lateral edges are smooth, we have his Ebalia. The Leucosise with an ovoid or nearly globular shell, and other- wise distinguished from several of the preceding by the claws being always longer than the body and thicker than the other feet, and by the tarsi being sensibly striate, may be divided thus: In some the front projects, or at least is not surpassed by the superior extremity of the buccal cavity. The outer branch of the external foot-jaws is elongated, and almost linear. Here the claws are slender, the hands cylindrical, and the fingers long. Sometimes the shell is nearly globular, and either very spiny, as in the genus Mrcania, or smooth as in Ilia. At others, the shell is suborbicular and depressed, as in the genus Persephona, or ovoid as in Myra. There the claws are thick, with ovoid hands and short fingers. They constitute the true Leucosiae of that naturalist. In the others, the supei'ior extremity of the buccal cavity out- reaches the front. The outer branch of the external foot-jaws is short, and arcuated; the shell rounded and depressed. This last division comprises his genus Phylira. Other considerations, founded on the proportions of the feet and the form of the external foot-jaws, strengthen these characters. The Leiicosie noyaic, Jlia nucleus, Leach; Cancer nucleus, Lin., Herbst., XI, 14, is common in the Mediterranean; its shell is globular, granulated on the sides and posteriorly; the front is notched; two teeth on the posterior margin, and two others (1) Leach Zool. Misc. Ill; Desmar., Consid. (2) Leucosia cylindrus, Fabr., Herbst,, II, 29 — 31. DECAPODA. 41 widely separated on each lateral margin; the posterior largest and spiniform, and situated above the origin of the posterior feet The sea coast of the western departments of France produces some other species which belong to the genus Ebalia, Leach(l). All the remaining ones are from India and America. Some fossil Leucosias are found in the East Indies. Three species have been described by M. Desmarest, two of which, according to him, are true Leucosias, Leach, and which are now living in the same countries, and peculiar to them. Our fifth section, that of the Tuigona, is composed of those spe- cies whose shell is usually triangular or subovoid, narrowed before into a point or kind of beak, generally uneven and rough, with late- ral eyes. The interval comprised between the antennae and the buccal cavity, is always nearly square, as long, or almost as long as broad. The claws, at least those of the males, are always large and elongated. The following feet are very long in a great number, and sometimes the two last even differ in form from the preceding ones. The third joint of the external foot-jaws is always nearly square or hexagonal, in those at least whose feet are of the ordinary length. The apparent number of the caudal segments varies. In both sexes of several it is seven; in others, however, the males at least, it is less. Several of these Crustacea are designated by the vulgar appella- tion of Jiraignees de mer or Sea-spiders, Although the species of this tribe are very numerous, but two have as yet been discovered except in a fossil state, one of which at least — Maia squinado — exists at the present day in a living state, and in the same localities(2). A first division will comprehend those whose second and follow- ing feet are similar, and which diminish progressively in size. From the latter we will form a first group of all those where the tail, either in both sexes, or in the females alone, is composed of seven segments. The third joint of the external foot-jaws is almost always square, and truncated or notched at the superior internal angle. Very large claws, particularly so when compared with the other feet, which are extremely short, directed horizontally and perpen- dicularly to the axis of the body as far as the carpus or joint im- mediately preceding the hand, then reflected anteriorly on them- (1) Malac. Brit., xxv. (2) See Desmar., Hist. Nat des Crust. Toss Vol. III.— F 42 CRUSTACEA. selves with the fingers bent, suddenly forming an angle; very short ocular pedicles, projecting but little, if at all, from their cavities; a stony and very uneven or spiny shell, designate the Parthenope, Fab. The lateral antennae of some are very short, not exceeding the length of the eyes; the first joint is entirely situated under the ocular cavities. If there are seven segments in the tail of both sexes, we have the genus Parthenope properly so called(l) of Leach. If that of the males presents but five, it is his genus Lambrus{2). The lateral antennae of the others are sensibly longer than the eyes; their first joint extends to the superior internal extremity of the cavities peculiar to these latter organs, and appears to be con- founded with the shell. The post-abdomen is always composed of seven segments. The claws of the females are much shorter than those of the opposite sex. The same naturalist distinguishes these Crustacea generically by the name of Eurynoma. But a single spe- cies is known which inhabits the English and French coasts(3). All the other Parthenopes, one excepted(4) are from the Indian Ocean. In the following ones, the claws always project, and their length, at most, is double that of the body; their fingers are not suddenly bent into an angle(5). Here the length of the longest feet — the second — barely exceeds that of the shell from the eyes to the origin of the tail. The under part of the tarsi is usually either dentated or spiny, or furnished with a ciliated fringe terminated like a club. We will commence with those whose ocular pedicles are very short, or of a mean length, susceptible of being entirely retracted (1) Par/Ztm.^omcfef, Fab.; liumph., Mas., IX, 1; Seba, III, xix,16, 17;Herbst., XIV, 88. (2) Panth. longimana. Fab.; Rumph., Mas., VIII? — P. giraffa. Fab.; Herbst., XIX, 108, 209; — P. lar, Fab.; — P. rubiis, Latr.; — Cancer conirarius, Herbst., Ix, 3; — P. macrocheles, Lat., Herbst., XIX, 107; — Cancer longimanus, L., fem., P. trigonomana, Lat.; Cancer prensor, Herbst., xli, 3. (3) Cancer asper, Penn., Brit. Zool.,IV: Eurynoma aspera. Leach, Malac. Brit., XVII. (4) Parthenope angulifrons, Latr., Encyc. Method.; Cancer longimanus, Ollvi. (5) The first joint of the lateral antennae appearing to form part of the shell, has been mistaken by several naturalists, the second having been considered by them as the first. DECAPODA. 43 within their cavities, and whose claws, at least in the males, are considerably thicker than the other feet. MiTHRAX, Leach. Robust claws; ends of the fingers like the bowl of a spoon; stem of the lateral antennae sensibly shorter than the pedicle; the tail composed of seven segments in both sexes. All the known species are from the American seas(l). * AcANTHONYX, Latr. A tooth or spiniform projection on the inferior side of the tibse; under part of the tarsi pilose, and as if pectinated; superior surface of the shell smooth. The tale of the males presents, at most, but six complete segments(2). Pisa, Leach. Claws of a mean size, with pointed fingers; tibae without any spine beneath, and the tail composed of seven segments in both sexes. As in the preceding subgenera, the lateral antennae are inserted at an equal distance from the fossulae that receive the intermediate ones, and from the ocular cavities, or rather nearer to the latter. These, as in the genus Naxia, Leach, (3) have two ranges of den- tations on the under part of the tarsi. Those have but a single row of dentations, or a simple fringe of thick claviform cilia, under the same joint. The latter constitute the genus Lissa of that author(4). Among those which have a range of dentations, the feet some- times gradually diminish in length, as happens in his Fisa(5) pro- perly so called, and at others, the third ones, in the males, become abruptly shorter than those which precede them, as in his Chori- nus{6). Pericera, Latr. The Pericerae, though approaching the Pisae in the form and pro- (1) Mithrax spinicindus, Latr.; Desmar., Consid., p. 150; — Cancer hispidus, Herbst, XVIII, 100; — Cancer aculeatus, Herbst., XIX, 104; — C. spinipes, ejusd., XVII, 94. The lachus hircus, Fab., is perhaps a cong-ener. (2) Maia glabra, Collect, du Mas. d'Hist. Nat.; 3:laia lunulata, Risso, I, 4; Li- binia lunulata, Desmar. (3) Fisaaurita, Latr., Encyc. Method. — P. monoceros, lb. (4) Pisa chiragra, Latr., Encyc. Method.; Desmai-., Consid. (5) Pisa xyphias, Latr., lb.; — ejusd. , lb. P. aries; — P. barhicornis; — P. corni- gera; — P. styx; — P. bicorntda,- — P. trispinosa,- — P. armata. Leach, Malac. IJrit., XVII; Cancer muscosus P, Lin.; — P. tetraodon. Leach, lb. xx. (6) Pisa /teros, Latr., Encyc. Method. 44 CRUSTACEA. portions of the claws, and the number of their caudal segments, are removed from them, as well as from the other anterior subgenera, by the insertion of their lateral antennas under the snout, and their approximation to the fossulce lodging the intermediate ones, being closer than to those which receive the ocular pedicles(l). In the two following subgenera the ocular pedicles are short or moderate, as well as in the preceding ones. But the claws, even those of the males, are hardly thicker than the following feet. The tail always consists of seven segments. In the Maia, Leach, The second joint of the lateral antennae seems to arise from the internal canthus of the ocular fossae. The hand and the joint which precedes it arc nearly of the same length. The shell is ovoid. This subgenus established by Lamarck, and originally consisting of a great number of species, comprises, at present, according to the method of Dr Leach, but one, the Cancer squinado, Herbst, XIV, 884, 5, Ivi; Inachiis cornutus. Fab. It is very common on the coast of France and in the Mediterranean, where it is called Jiraignee de mer. It is one of the largest of the European Crustacea, and the Maia of the ancient Greeks, figured on some of their coins. They attributed great wisdom to it, and considered it as sensible to the charms of music. • MicippE, Leach. The first joint of the lateral antennae curved, dilated at its supe- rior extremity into a transverse and oblique blade, closing the ocular fossae; the ensuing joint inserted under its superior margin. The shell, viewed from above, appears widely truncated before; its an- terior extremity is inclined, and terminates in a sort of clypeus or dentated rostrum(2). The » Stenocionops, Leach, Is distinguished from all the other subgenera of this tribe by (1) Maia taurus. Lam.; Cancer cornudo, Herbst., lix, 6. N.B. The genus JlmatUa of M. P. Roux, Hist, des Crust, de la Mediterr., &c., liv. I, does not differ from my Pericera — it even appears to me to have the same type. The Lithographic plates which accompany this work are distinctly and faithfully executed. (2) Cancer a-istatus, L.; Tlumph., Mus., V1T[, 1, the male. — Cancer phylira, Herbst.. lyiii, 4; Desmar. Consider., XX, 2. DEC APOD A. . 45 long and slender ocular pedicles which protrude from their fossu- 1^(1). There, the under surface of the feet presents neither ranges of den- tations nor claviform cilia. Those of the first pairs, at least, are one half longer than the shell, and frequently much longer. The body- is usually more abbreviated than in the preceding subgenera, being either nearly globular, or formed like a shortened t^g. A species of this tribe, — 31aia retuja, Coll. du Jard. du Roi, whose shell is woolly and forms a truncated ovoid, or is obtuse anteriorly; whose strongly curved elongated ocular pedicles are received into fossulae situated under the lateral margin of the shell ; whose carpus is elongated, as in Maia, pre- sents another character which exclusively distinguishes it, viz. the length of the feet seems to augment progressively from the second pair onwards, or at least to differ but little. It is the type of the genus CamposciAj Leach. In the others, as usual, the length of the feet progressively di- minishes from the second pair to the last. In some of them, the ocular pedicles, although much shorter than in the Stenocionops, are always salient, and the third joint of the pedicle of their lateral antennae is as long, or even larger, than the preceding one, the antennas themselves terminating in a long seta- ceous stem. They approach the Micippes; such is the Halimus, Latr.(2) In those which constitute the two following sub-genera, the ocular pedicles are susceptible of being entirely retracted within their fos- sulae, and are protected posteriorly by a dentiform projection, or angle, of the lateral edges of the shell. The second joint of the pe- duncle of the lateral antennas is much larger than the following one; they are terminated by a very short stem resembling an elon- gated stylet. Hyas, Leach. Lateral edges of the shell dilated behind the ocular cavities which are large and oval; external side of the second joint of the lateral (1) Cancer cervicornis, Herbst, Iviii, 2, from the Isle of France. M. Desmarest was mistaken inciting-, as the type, Consid. Gen. sur les Crust., p. 153, the Maia taurus, Lamarck. (2) Two species, one of which appears to be allied to the Cancer supercillosus, L., Herbst, XIV, 89. 46 CRUSTACEA. antennae compressed and carinated; ocular pedicles, when erected, entirely exposed. The body is sub-ovoid(l). In the LiBiNiA, Leach, The ocular fossulae are A'ery small and nearly orbicular, and the ocular pedicles are very short, and but very slightly exertile. The second joint of the lateral antennae is cylindrical, and not compress- ed, or but very slightly so. The body is nearly globular, or trian- gular. We will unite the Doclsea and the Egeria of Leach, to his Li- BINIiE. In his Libinise, properly so called(^2), the claws of the males are thicker than the two following feet and almost as long. The length of the longest does not exceed twice that of the shell. The claws of the male Doclaea(3) are much shorter than the two following feet. The length of the latter is hardly more than once and a half that of the shell, which is nearly globular and always co- vered with a brown or blackish down. In the Egeri3e(4) the claws are filiform and the hands much elon- gated and almost linear. The following feet are five or six times longer than the shell. The body is triangular. Having reviewed all the sub-genera of this tribe in which the feet subsequent to the claws are of a similar form, and in which the tail, of the females at least, and most generally in both sexes, is composed of seven complete joints or segments, we now pass to those in which it never consists of more than six. The feet are usually long and filiform, as in the last sub-genera. With the exception of the Lep- topi, these Crustacea are also removed from the preceding by the form of the third joint of the external foot-jaws. It is proportion- ally narrower, and contracted at base, and the ensuing joint appears to be inserted in the middle of its superior margin, or more exter- nally. The following sub-genus differs from those which succeed to it, in the tail of the males, where we only find three segments. The form of the third joint of the external foot-jaws appears to me the same as in the preceding sub-genera. (1) Cancer araneus, L.; Leach, Make. Brit., XXI, A; Herbst., XVII, 59;— Hyas codrdata, Leach, lb., xxi, 15. (2) Libinia canaliculata, Say, Journ. Acad. Nat. Sc. Philad. vol. I, p. 77, iv, 1; — L. emarginata. Leach, Zool. Misc., cviii. (3) Doclxa Ii{sso7inii, Leach, Zool. Misc., Ixxiv. The Inachus ovis and the T. hybridus, Fab., should be referred to it. (4) Egeria indica, Leach, Zool. Misc., Ixiii; Inachus spinifer. Fab. DECAPODA. 47 Leptopus, Lam. Tail of the females composed of but five segments; the body con- vex and feet very long. But a single species is knoAvn which is part of the collection of the Museum d'Histoire Naturelle, where it is called Maia longipes. Doctor Leach proposed to designate this genus by the name of Ste- nopus, a denomination we have not adopted, inasmuch as it is al- ready appropriated to another. That of Leptopus, Lam., is com- posed of several species, which, the above mentioned one ex- cepted, according to the characters here given, must be excluded from it. If we except some species of Hymenosomse in which the tail pre- sents but four, or at most five, distinct segments, that part of the body consists of six in all the following sub-genera, either in both sexes, or in the males. The third joint of the external foot-jaws is sometimes in the form of an inverted triangle or of a posteriorly narrowed oval, and sometimes in that of a heart. The ensuing joint is inserted in the middle of its superior margin, or rather more out- wards than inwards. Some of them, such as the three following sub-genera, approach those of which we have just spoken by the almost isometrical, or at least transversal form of the epistoma. The base of the interme- diate antennae is but a short distance from the superior margin of the buccal cavity. One of these sub-genera is distinguished from the others by the flatness of the shell, and by the superior extremity of the first joint (free in several) of the lateral antennae, which does not extend be- yond that of the ocular pedicles. Such is the Hymenosoma, Leach. The shell is triangular or orbicular(l). The species are gene- rally small and peculiar to the Indian Ocean and coast of Australia. The number of caudal segments varies, but never extends beyond six. In the two following sub-genera, the shell is more or less convex, always triangular and terminated before in a rostrum. The first joint of the lateral antennae, always fixed, forms a ridge or salient line between the fossulse of the intermediate antennse and that of the eyes, and which is prolonged beyond the end of the ocular pedicles. In the (1) Hymenosoma orbicularis, Desmar., Consid., xxvi, 1 48 CRUSTACEA. Inachus, Fab., The tail is always composed of six segments; all the tarsi are nearly straight, or but slightly arcuated; the ocular pedicles are smooth, susceptible of being concealed within their fossulae, and there is a tooth or spine, at least in the males, at the posterior ex- tremity of the latter cavities. Doctor Leach has considerably re- duced the original extent of this group(l). AcHiEus, Leach. Six segments in the tail, but the four posterior tarsi are arcuated or falciform; the ocular pedicles are always salient and present a tubercle anteriorly(2). Next come those in which the epistoma is longer than it is broad, shaped like an elongated triangle truncated at the apex, and in whicli the origin of the mediate antennae is separated by a considerable space from the superior margin of the buccal cavity. The ocular pedicles are always salient when the head is triangular and termi- nated in a point more or less bifid or entire. Stenorhynchus, Lam. — Macropodia, Leach. Six caudal segments in both sexes; anterior extremity of the shell bifid(3). Leptofodia, Leach. Five segments in the tail of the male; one more in that of the fe- male. The shell is prolonged anteriorly into a long, entire, and dentated point(4). The latter Trigona differ from the preceding in the dissimilitude of their posterior feet. (1) Cancer dodecos P L.; Inachus scorpio, Fab. ; — Inachus Dorsettensis, Leach, Ma- lac. Brit., xxii, A; — Inachus phalangium, Fab.; Inachus dorynchus. Leach, lb.,. xxii, 7, 8; — Inachus leptorinchus, ejusd., lb., xxii, B; Cancer tribulus, L. ? Near the Inachi comes a ne\T genus lately established by M. Guerin, called Eurypode, minutely described and carefully figured, Mem. du Mus. d'Hist. Nat. XVL It ap- proaches that of Inachus, but the ocular pedicles are always salient; the post-ab- domen is composed of seven completely separate segments in both sexes, and the penultimate joint of the feet, or the metarsus, is inferiorly dilated and compressed. (2) Jlchmis Cranchii, Leach, Malac. Brit, xxi, C. (3) Macropodia ienuirostris, hesich, Malac. Brit, xxiii, l—5;Inachuslongirostris? Fab. ; — Maa-op. phalangium, Leach, lb., xxiii, 6. (4) Inachus Sagittarius, Fab.; Leach, Zool. Misc., Ixvii. DECAPODA. 49 Pactolus, Leach. The four or six anterior feet simple, or without forceps. The in- ternal extremity of the penultimate joint of the four posterior ones is prolonged into a tooth, forming with the last joint a forceps or didactyle hand. The form of the shell is that of the Leptopodise, and the tail pres,ents the same number of segments; but the feet are much shorter; those of the third pair were wanting in the individual which served as the type of this section(l}. LiTHODES, Lat. The Lithodes, as to the form of the first eight pairs of feet, re- semble the other Trigona; their length, however, seems progressively to increase from the second to the fourth, but the two last are very small, bent, but slightly visible, beardless, and apparently useless. The tail is membranous Avith three crustaceous and transverse spaces on the sides and another on the end, representing the seg- mentary divisions. The eyes are approximated inferiorly. The ex- ternal foot-jaws are elongated and salient, and the shell is triangu- lar, extremely spinous and terminated anteriorly by a dentated point. These Crustacea are peculiar to the Arctic Seas(2). Our sixth section, that of the Cryptopoda(3) consists of Brachyura remarkable for a vaulted projection of the posterior extremities of their shell under which their feet, the two anterior or the claws ex- cepted, can be completely retracted and concealed. The shell is nearly semi-circular or triangular. The superior edge of the forceps is more or less elevated and notched in the manner of a crest. In those species where they are largest, they cover the anterior part of their body, and hence the naiyie of Coq de mer (Sea Cock), and Crabe honteux (Bashful Crab), which have been given to some of them. One sub-genus of this section, that of ,Mthra being closely allied by other characters with the Parthenopes of Fabricius, the first sub-genus of the preceding section, it follows, in a natural order (1) Fadolus Boscii, Leach, Zool. Misc., Ixviii. (2) Cancer maja. L-; Parthenope maja. Fab.; Inachus maj'a, Id. ^ lAthodes arc- tica, Leach, Malac. Brit., xxiv. See also the Maja camptschensis. Tiles., Mem. Acad. St. Petersb., 1812, V, VL. (3) Several of the Arcuata, such as the Hepati, Mursiae, Matutae, among the swimmers, have a crested forceps, and seem to be naturally allied to the Crypto- poda, so that this section should be placed higher in the scale. The same obser- vation applies to the last one, or that of the Notopoda, for some of them approach the Arcuata, and others the Orbiculata and the Trigona. Vol. III.— G 50 CRUSTACEA. the Cryptopoda should be placed between the Orbiculata and the Trigona. Calappa, Fabr. An extremely convex shell; the forceps triangular, strongly com- pressed, dentated superiorly like a crest, and perpendicularly cover- ing the anterior part of the body, during the contraction of the feet. The third joint of the external foot-jaws is terminated like a hook, and the superior extremity of the buccal cavity is contracted and divided longitudinally into two cells by a septum. n most of them, the two posterior and lateral dilatations of the shell are incised and dentated. One species, the Calappe migrane, — Cancer granulatus, L.j Calappa granulata^ Fab.; Herbst., XIII, 75, 76, vulgarly styled Coq de mer and Crabe honteux, is found in the Mediterranean, The shell is reddish and marked with two deep sulci, and une- qual tubercles of a carmine red. That portion of the lateral margin which precedes the posterior dilatations, is at first nearly entire, and terminates by four very short teeth, the two first being most strongly marked; those of the edges of the dilatations are large, and six in number, two on the posterior margin, and the others lateral. There are two others on the front. The forceps are also furnished with red tubercles, and their crest is formed by seven teeth, the superior of which are acute(l). The others, such as the C. voute — Cancer calappa, L.j Calappa fomicata, Fab.; Herbst., XII, 73, 74, have the marginal dila- tations of the shell entire. This species inhabits the seas in the vicinity of Australia and the Moluccas. ^THRA, Leach. The iEthrae diff'er from the Calappse in their very flat shell, in their forceps, which are not raised perpendicularly, and which do not overshadow the forepart of their body, and in the almost square form of the third joint of the external foot-jaws. (1) In this division come the following species of Fabricius: C. iuberculata, Herbst., XlII, 78; Iviii, 1?— C. lophos, Herbst., Xlll, 77;— C. cristaius, Herbst., xl, 3; — C. marmoratus, Herbst., xl, 2 — The Guaja apara, Pison and Marcgr., should probably be referred to this species, and according to the citation ofBarere is the Crabe des paletuviern of the colonists of Cayenne. The Cancer Jiepaticus of Linnseus is also a Calappa. DECAPODA. 51 Sometimes(I) the shell is a transversal oval, and at others(2) forms a short and very wide triangle laterally dilated and rounded. The claws are but slightly elongated, and are tolerably thickj here they are longer, angular, and remind us, as does also the form of the shell, of the Parlhenopes. These latter species might constitute a sepa- rate subgenus. Finally, our last and seventh division, that of the Notopoda, con- sists of Brachyura, whose last four or two feet are inserted above the level of the others, or which appear to be dorsal and look up- wards. In those where they terminate by a sharp hook, they are usually employed by the animal in seizing various bodies, such as shells, Alcyonii, &c., with which it covers itself. The tail consists of seven segments in both sexes. The tail of some of them, as in other Brachyura, is folded under, and their feet terminate in a sharp hook and are not fitted for nata- tion. Here the shell is nearly square, and terminates anteriorly in an advancing and dentated point, or it is sub-ovoid or truncated before. In the HoMOLA, Leach, The eyes are supported by long pedicles closely approximated at base, and inserted under the middle of the front. The two posterior feet are alone turned up. The claws are larger in the males than in the females. The shell is extremely spinous, with a dentated projection on the middle of the front. The superior foot-jaws are elongated and sa- lient. These Crustacea inhabit the Mediterranean, and were designated by Aldrovandus under the name of Hippocardni; they are the Thel- xiopes of Rafinesque. Some of the species attain a great size(3). DoRipPE, Fab. The eyes widely separated and placed at the anterior and lateral angles of the shell; the four posterior feet turned upj the claws short (1) ^thra depressa. Lam., Hist, des Anim. sans Verteb. ; Cancer scruposus, L.; Cancer polynome, Herbst, liii, 4, 5; Desmar., Consid., X, 2. (2) Parthenope fornicata. Fab. (3) Homola spinifrons. Leach, Zool. Misc., lxx,xviii; Cancer spinifrons. Fab. See the article Homole, Nouv. Diet. d'Hist. Nat. Ed. II, and Desmar., Consider., XVII, 1. The Dorippe Cuvieri, Risso, belongs to this subg'enus. 52 CRUSTACEA. in both sexes; the shell ovoid, widely truncated, without any projec- tion like a rostrum, and flattened. As remarked by Desmarest, we may observe on each side and above the origin of the claws an oblique fissure resembling a button- hole, longitudinally intersected by a diaphragm, ciliated, like itself, on the margin that communicates with the branchioe, and affording an issue to the water that bathes them. Three species are found in the Mediterranean(l); the others inhabit Oriental seas, and one of them B. quadridens^ Fabr., Herbst., X, 70, is also obtained there in a fossil state. There, the shell is sometimes nearly orbicular, or globular, and sometimes arcuated anteriorly and narrowed posteriorly, and den- tated or spinous on the sides. The eyes are situated near the middle of the front and placed on short pedicles. Dromia, Fab. The four posterior feet inserted in the back, and terminated by a double hook; the shell suborbicular or nearly globular, convex and woolly, or very hairy. With their hind feet they seize upon Alcyonii, shells, and other bodies, beneath which they shelter themselves, transporting them wherever they go. The most common species, — Cancer dormia, L., Rumph., Mus., XI, 1; Herbst., XVIII, 103, is found in every sea, that of the North excepted. It is covered with a brown down, and has five teeth on each lateral margin and three in front. The fin- gers are stout, deeply dentated on the two edges, and partly rose-coloured. Some authors say that it is venomous. The Death's Head, — Cancer caput mortuum^ L. ; Dormia clype- ata, Act. Ilafn., 1802, is smaller, more convex, almost globular, with three teeth on each side in its anterior margin, and has a short front, emarginate in the middle and laterally sinuous. It is found on the coast of Barbary(2). Dyxomene, Lat. The tAvo posterior feet much smaller than the others, alone dorsal, and apparently unarmed; the shell widened, and nearly resembling a reversed heart truncated posteriorly, like that of the last Quadri- (1) Dorippe lanata; Cancer hniatus, L.; Desmar., Consider., XVII, 2; — D. affinis, Id.; Herbst., XI, 67; — Cancermascarone, Herbst., XI, 68. (2) For the other species see Desman, Comid. Gen. sur la Classe des Cru/st., p. 136, et seq. DECAPODA. 53 latera, and simply pubescent. The ocular pedicles are longer than those cf the Dromiae. But a single species, the Bynomene hispide, Desmar., Consid., XVIII, 2, is known; it is found at the Isle of France. The last Notopoda differ from the preceding in the feet, all of which except the claws, terminate in a fin, and from all the Brachy- ura in the extension of their tail. Such is the Ranina, Lam., In which the elongated shell is gradually narrowed from before backwards, and usually resembles a reversed triangle with a den- tated base. The ocular pedicles are extended, and the lateral an- tennas long and projecting. The external foot-jaws are similarly lengthened and narrow, and the extremity of the third joint is com- pressed into a point. All the feet are closely approximated, or almost contiguous at their origin, and from the fourth pair ascend towards the back; the two last, however, are alone on it. The for- ceps are compressed, have the figure of a reversed triangle, and are dentated; the fingers are suddenly flexed. These Crustacea are closely allied to the Albunese of Fabricius, the first sub-genus of the following family, and thus form the passage from the Brachyura to the Macroura. From the approximation of the feet it is even probable that the genital orifices of the female are situated as in the Macroura. According to Rumphius, they not only leave the water, but even climb to the tops of houses; from the form of their feet, however, this appears impossible, or at least very improbable. A fossil species was described by Aldrovandus, which the Abbe Ranzani and M. Desmarest have since made better known(l). (1) Ranina Mdrovandi, Ranz., Mem. di Stor. Nat.; Desmar., Hist. Nat. des Crust. Foss., Vf, xi, 1. The fig-, x, 5, 6, appears to us to belong to a Hippa rather than to a Ramina; — Ramina serrata. Lam. ; Cancer raninus, L. ; Mbunea scabra. Fab.; Rumph., Mus., VII, T.V.; — Ranina dorsipes, 'L2sa,-^ Albunea dorsipes. Fab.; Rumph., Mus., X, 3; Desmar., Consider., XIX, 2. The genus Symethis, Fab., is unknown to us, but we presume it is allied to the Raminse, or to the first subgenera of the subsequent family. 54 CRUSTACEA. FAMILY II. MACROURA.— ExocHNATA, Fab. In the Decapoda Macroura, the end of tlie tail is provided with appendages(l) whicli most frequently form a fin on each side : the tail itself is at least as long as the body, extended, exposed and simply curved towards its posterior extremity. Its under surface usually presents in both sexes five pairs of false feet, each terminated by two laminae, or as many fila- ments. This tail is always composed of seven distinct seg- ments. The genital orifices of the females are on the first joint of the third pair of feet. The branchiae are formed of vesicular, bearded and hairy pyramids, arranged in several of them, either in two rows, or in separate fasciculi. The an- tennae are generally elongated and salient. The ocular pedi- cles are usually short. The external foot-jaws are mostly narrow and elongated, resembling palpi, and do not wholly cover the other parts of the mouth. The shell is narrower and more elongated than that of the Brachyura, and usually terminates by a point in the middle of the front. For more minute details we refer the reader to the pre- cited memoir of Messrs Audouin and Edwards. These gen- tlemen have observed a character in the Lobster, — testacies (1) These appendages consist of three pieces, one of which serves as a base or pedicle to the others, and is articulated with the penultimate segment; the latter, in conjunction with them, usually forms a fan-like fin; but in the last subgenera of this family these appendages are replaced by setaceous filaments. The false feet under the tail are similar in their structure to tjiese natatory appendages. In the first subgenera they frequently do not exceed three or four pairs, and are smaller, or even null in the males, the two anterior ones always excepted; the Paguri, as it appears to me, only have them on one side: the terminal pieces are often une- qual. In the succeeding ones, however, these feet are longer, and always form five pairs; the ova attached to them, and they are used by the animal in swimming. We observe that in the Macroura, where they are fewer in number, or less de- veloped, as in those which we term the ^woma/a, the peduncle of the intermediate antennx is longer in proportion than in the others, and that the two or four last four feet are smaller. These Crustacea, in some respects, seem also jillied to the Brachvura. DECAPODA. 55 marinus, Fab. — which, if it applied to the other Macroura, would be decisive; it is, that besides the two venous sinuses of which we have spoken in our general observations upon the order, there is a third, situated in the sternal canal be- tween the two preceding ones and extending from one end of the thorax to the other. This curious arrangement, accord- ing to them, establishes a connexion between the venous sys- tem of the Macroura, and that of the Stomapoda. The Macroura never quit the water, and, with the excep- tion of a small number, are all marine Crustacea. In imitation of De Geer and Gronovius, we will arrange them in a single genus(l), that of Astacus, which we divide in the fol- lowing manner: Some, by the proportions, figure, and uses of their feet, of which the first, or at least the second pair, are in the form of claws, and by the subcaudal situation of their ova, evidently approach the preceding Crustacea, and approximate still more closely to those commonly known by the names of Craivfish, Lobster, and Shrimp. The feet of the others are very slender, and are furnished with an exterior and elongated appendage or branch, which seems to double their number. They are exclusively adapted for natation, and none of them terminates in a forceps. The ova are situated between them, and not under the tail. We will subdivide the former into four sections j the Anomala, the LocustjE, the Astacina, and the Carides. The latter will compose the fifth and last sections of this family, and of the Decapoda, or that of the Schizopoda. In the first, or the Anomala, the two or four last feet are always much smaller than the preceding ones. The under part of the tail is never furnished with more than four pairs of appendages or false feet(2). The lateral fins of the end of the tail, or the pieces which (1) The sections which we are about to describe might foi-m so many generic divisions, having for their basis the genera of Fabricius. (2) With the exception of the two that are anterior, these appendages in the males are mere rudiments, or are even wanting, a character common to the Gala- theae, Scyllari, and Palinuri. We should also observe that in these three sub- genera the caudal fins are thinner or almost membranous at their posterior extre- mity. In this section, as well as in the Galatheac, the thoracic portion to which the two posterior feet are attached forms a sort of petiole, so that these feet seem to be annexed to the tail. 56 CRUSTACEA. represents them, are thrown on the side and do not form with the last segment a flabelliform fin. The ocular pedicles are generally longer than those of the Ma- croura belonging to the following sections. Here (the Hippides, Latr.), all the superior teguments are solid. The two anterior feet sometimes terminate in a monodactyle hand, or one without a finger, in the manner of a palette, and sometimes in a pointy the six or four following ones end in a fin; the two last are filiform, reflexed, and situated at the inferior origin of the tail. The latter becomes suddenly narrowed immediately after the first segment which is short and broadj the last is in the form of an elongated triangle, and the lateral appendages of the penultimate in that of curved fins. There are four pairs of sub-caudal appendages, composed of a very slender and filiform stem. The antennae are very pilose or strongly ciliatedj the lateral first incline to the interme- diate, and are then arcuated or contorted outwards. Albunea, Fabr. The two anterior feet terminated by a very compressed triangu- lar, monodactyle hand; the last joint of the following ones falciform. The lateral antennae are short, and the intermediate ones are termi- nated by a single long and setaceous filament. The ocular pedicles occupy the middle of the front, and form, together, a sort of flat trian- gular snout, with the external sides arcuated. The shell is almost plane, and nearly square; the posterior angles are rounded, and their anterior margin finely dentated. The only well known species, Cancer symnista^L..; Albimea symnista, Fabr., Herbst., XXII, 2; Desmar., Consider., xxix, 3, inhabits the Indian Ocean(l). If the Cancer carahus of Linnaeus belong to the same subgenus, a species would be found in the Mediterranean. HippA, Fab. — Emerita, Gronov. The two anterior feet terminated by a strongly compressed, nearly ovoid and adactyle hand; the lateral antennae much shorter than the intermediate, and contorted; the latter terminated by two short, obtuse filaments placed one on the other; the ocular pedicles (1) M. Desmarest hesitatingly places the genus Posydon of Fabricius, who speaks of two species, near the Albunese; but according to the latter the anterior antennae are bifid, a character which does not belong to the Albunes. Owing to the imperfect manner in which he describes this genus, we are not able to recog- nize it, or to appreciate its affinities. DECAPODA. 57 long and filiform, and the third joint of the foot-jaws very large and laminiform, emarginated at the end and covering the ensuing joints. The shell is nearly ovoid, convex, and truncated at both ends. The last joint of the second feet and of the two following pairs is triangular, but approaching, in the latter at least, to the form of a crescent; the two last of the fourth pair are turned up, and laid on the two preceding ones; the first segment of the tail is marked with two impressed and transverse lines(l). Remipes, Lat. The two anterior feet elongated, the last joint conical, compressed, and hairy; the four antennse closely approximated, very short, and nearly of an equal length, the intermediate ones terminated by two filaments; ocular pedicles extremely short and cylindrical; external foot-jaws in the form of small claws, thinned and arcuated at the end, and terminated by a stout hook. The shell is shaped like that of the Hippse. The last joint of the second and third feet forms a triangular blade, with an emargination in its external side; the same joint of the fourth is triangular, narrow, and elongated. As in the Hippse, the first caudal segment presents two impressed and transverse lines. Two species are known; one from the Australian Seas(2), and the other from the Antilles, and the coast of Brazil. There (the Pagurii, Latr.), the teguments are somewhat crusta- ceous, and the tail is most commonly soft, contorted, and in the form of a sac. The two anterior feet terminate in a didactyle hand, the four following ones in a point, and the four posterior, which are shorter, in a sort of forceps or little didactyle hand. The first joint of the peduncle of the lateral antennae presents a pointed or spiniform appendage or projection. These Crustacea, termed Carcinion by the Greeks, and Cancelli by the Latins, usually inhabit empty univalve shells. Their tail, that of the Birgi excepted, presents but three false feet, (in the females only), situated on one of the sides, each of which is divided into two filiform and hairy branches. The three last segments are suddenly narrowed. In some of them, such as the (1) Hippa adaciyla,Fa.h.^ H. emeritus, 16..-, Cancer emeritus, "L.; Emerita, Gro- nov., Zoop., xvii, 8, 9; Herbst., xxii, 3; Desmar., Consider., xxix, 2, in the seas of both Indies. (2) Remipes testudinarius, Latr.; Desmar., Consid., xxix, 1; Cuv., Regne Ani- mal, IV, xii, 2. Vol. III.— H 58 CRUSTACEA. BiKGUs, Leach, The tail is tolerably solid, siiborbicular, and is furnished beneath with two rows oF laminiform appendages. The fourth feet are but a little smaller than the tAvo preceding ones^ the two last are folded and concealed, their extremities being received into a depression at the bottom of the thorax; the fingers at the extremity, as Avell as those of the penultimate pair, are hairy or spinous. The claws except- ed, all the feet are visibly separated at their origin. The thorax has the figure of a reversed heart, and is pointed anteriorly. It appears that from their size, the form of their tail, and the more solid consistence of their teguments, the Birgi are unable to shelter themselves in shells. They must retreat to holes, or fissures in the rocks. The best known species. Cancer latro, L., Herbst. XXI Vj Rumph., Mus., IV; Seba, Thes., Ill, xxi, 1, 2, according to the Indians, feeds on cocoa-nuts which it obtains during its noctur- nal excursions for that purpose(l). In the others, or the Pagurus, Fab., The last four feet are much shorter than the preceding ones, and the forceps are covered with granules. The tail is soft, long, cylin- drical, narrowed near the extremity, and has usually but a single roAV of filiform ovifcrous appendages. The thorax is ovoid or oblong. With the exception of some species domiciliated in sponges, Ser- pulae and Alcyotiii, they all inhabit univalve shells, whose aperture they close with their anterior claV/s, and most frequently with one of their fingers, which is usually larger than the other. It is asserted that the female spawns twice or thrice in the year. Some species, C.enobita, Latr. ; distinguished from the others by their projecting antennae, of which the mediate are nearly as long as the external or lateral, and are furnished with elongated filaments, whose thorax is ovoido-conical, narrow, elongated, strongly com- pressed on the side, with the anterior cephalic portion shaped like a heart, establish their domicil in terrestrial shells on rocks near the sea, whence, at the approach of danger, they roll down with them(2). (1) Pagurus laticaudfi, Cuv., Regn., Anim., IV, xii, 2; Desmar., Consider., p. 180, from the Isle of France. Very curious facts relating- to the anatoniy of the preceding' species have been published by M. GeofFroy Saint-Hilaire, from which however we do not draw similar conclusions. (2) Pagurus clypeatus. Fab.; Herbst., xii, 2. DECAPODA. 59 The true Paguri — Pagurus, Latr. — on the contrary, have the me- diate antennae curved, niucli shorter than the lateral ones, with the two filaments short, the superior forming an elongated or subulated cone: the anterior division of the thorax is square, or forms a re- versed and curvilinear triangle. They inhabit marine shells. The Hermit^ — Cancer Bernhardus, L., Herbst., XXII, 6; Fa- gurus streblonyx, Leach, .Malac. Brit., XXVI, 1 — 4, — is of a mean size. Its two claws are bristled with spines, with the for- fceps almost in the shape of a heart, the right one being the largest. The last joints of the ensuing feet are also spinous. It is very common in European seas. A second but fossil spe- cies, the Fagure de Faujas, — Desmar., Hist. Nat. des Crust. Foss., XI, 2, — is closely allied to it. A third species, the Fagurus angulafus, Risso, Crust, de Nice, I, 8; Desmar., Consider., XXX, 1, is remarkable for its forceps, Avhich are strongly sulcated with longitudinal ridges. The right one is the largest(l). A fourth from the same sea is removed from the preceding by several characters, and merits the distinction of forming a separate subgenus, the Prophylax, Latr. The tail, with the exception of the superior surface of the three last segments, instead of being soft and arcuated and having but a single range of oviferous filaments, is covered with a coriaceous tegument, is straight, and is only curved beneath at its extremity^ its inferior surface presents a groove and two rows of false feet. The body also is linear, and the two lateral appendages of the end of the tail are almost equal, the larger divi- sion being foliaceous and ciliated. The last four feet are slightly granulated at their extremity, and appear to be terminated by a sin- gle finger, or at least are not distinctly bifid. Perhaps we should refer to this division those Paguri which inhabit the Serpulae, and Alcyonii, such as the Fagurus tuhularius, Fab. In all the following Macroura, the two posterior feet at most are smaller than the preceding ones. Most generally the sub-caudal false feet form five pairs. The teguments are always crustaceous. The lateral fins of the penultimate segment of the tail, and its last, form a common one arranged like a fan. The two subsequent sections possess a common character, which (1) For the other species see the article Pagure, Encyc. Method.; the Atlas d'Hist. Nat., of the same work; Desmarest, Consider. Ge^ier. sur la Classe des Crust. ; the plates of the Voy. de Freycinet. We should observe that in the figure ofthe Cancer megistos, Herbst., LXI, 1, the tail is false; this arises from the fact that the tail was wanting in the individual from which the drawing was made, the artist supplying it by copying the fin-tail of an ordinai-y Macroura. 60 CRUSTACEA. separates them from the fourth or that of the Carides. The an- tennse are inserted at the same height, or on a level; the peduncle of the lateral ones, when accompanied by a scale, is never entirely co- vered by it. There are frequently but four pairs of sub-caudal false feet. The two mediate antennae are always terminated by two fila- ments only, usually shorter than their peduncle, or scarcely any longer. The external leaflet of the natatory appendages of the pe- nultimate segment of the tail is never divided by a transverse suture. In our second section, or the LocusTiE, so called from the name Locusta given by the Latins to the most remarkable Crustacea of this division, and from which is derived that of Langouste applied to them in France, there are never more than four pairs of false feet. The posterior extremity of the fin that terminates the tail, is always nearly membranous, or less solid than the rest. The peduncle of the mediate antennae is always longer than the two terminal fila- ments, and more or less bent or geniculate; the lateral ones are never furnished with scales; sometimes they are reduced to a single peduncle which is dilated, very flat, and in the form of a crestj sometimes they are large and long, terminating in a point and bris- tled with spines. All the feet are nearly similar and end in a point; the two first are merely somewhat larger; their penultimate joint and that of the two last are at most unidentated, but without forming with the last a perfectly didactyle hand. The pectoral space in- cluded between the feet is triangular; the thorax is almost square or sub-cylindrical, and without any frontal prolongation or rostrum. ScYLLARUS, Fab. The Scyllari, or Sea-Grasshoppers as they are called, present a very unusual character in the form of their lateral antennse; the stem is wanting and the joints of the peduncle, very much dilated trans- versely, form a large, flattened, horizontal crest more or less den- dated. The external branch of the sub-caudal appendages is terminated by a leaflet; but the internal one, in some of the males, is a mere tooth. Doctor Leach has established three genera of them, founded on the proportions and form of the thorax, the position of the eyes, and some other parts. They are, 1. ScYLLARus, where the thorax is as long as it is broad or longer, and without any lateral incisure, the eyes always situated near its ante- rior angles; the penultimate joint of the two posterior feet uniden-' tated in the females. They excavate holes in the clayey soil near the shore which serve them for habitations. DECAPODA. 61 In one of them, the Scyllare ours; Cancer arctus^ L.; Cigale de mer, Rondel., livr. XIII, chap. VI j Herbst., XXX, 6, the ex- ternal or lateral antennae are much dentated. The thorax is marked with three longitudinal and dentated ridges, and the superior surface of the tail sculptured, but its lateral margin not crenulated. The other, Scyllarus seqiiinoxialis, Fab.; Scyllarus orientalis, Risso; Squille large, or the Orchetta, Rondel.; Gesn., Hist, des Anim., Ill, p. 1097, is large, shagreened, and without ridges. The crests are edentated, and the margin of the segments of the tail crenulated. Its flesh is highly esteemed and the ova are of a vivid red. 2. Thenus, where the fore part of the thorax is broader than it is long, each lateral margin deeply incised, and the eyes are placed at its anterior angles(l). 3. Ibacus, only differing from Thenus in the position of the eyes, which are approximated to the origin of the intermediate antennae. In an Australian species, /6acMS Pronii, Leach, Zool. Miscel., CXIX; Desmar., Consid., XXX, 12, the exterior lateral mar- gin of the third joint of the external foot-jaws is transversely striated and notched in the manner of a crest(2). In the Palinurus, Fab. The lateral antennae are large, setaceous, and bristled with spines. Of these Crustacea, called Carabos by the Greeks, and Lociistahy the Latins, and on which Aristotle made several important observa- tions, some attain a length of nearly two metres, the antennae in- cluded. The species found in European seas remains in deep water during the winter, and only visits the coast on the return of spring. Rocky localities are its favourite haunts. It subsequently deposits its ova, which are of a beautiful red colour, whence their name of Coral. At this period more males are taken than females, while after the spawning season the latter are most abundant. According to Risso a second copulation, followed by another production of ova, takes place in the month of August. The Palinuri are disseminated throughout all the seas of the temperate and intertropical zones, but are particularly abundant in the latter. Their shell is rough, covered {\) Thenus indicus, Les^ch; Sci/llai;us orienfalis. Fab.; Rumph., Mus., II, D-; Herbst., XXX, 1; Encyc, Atl. d'Hist. Nat., CCCXIV; Desmar., Consid., XXXI, 1. (2) Add Scyllarus antarcticus; Fabr., Herbst., xxx, 2i Rumph., Mus., JI, D. See the article Scyllare, Encyc. Methodique. 62 CRUSTACEA. with prickles, and armed in front with stout, projecting, and more or less numerous spines or teeth. Its colour, as also that of the tail, consists of an agreeable mixture of red, green, and yellow. The tail frequently presents transverse bands or spots, sometimes ocellated, arranged in regular series. Their flesh, that of the females particu- larly, before and. after the spawning season, is highly esteemed. In the species taken on the coast of France, and probably in others, the extremity of the penultimate joint of the two posterior feet of the female is provided with a tooth or spur peculiar to the sex. The same ol)servation applies to the Scyllari. PaUnurus quadriconiis, Fab.; Astacus eZe/)/«as, Herbst., xxix, 1; Leach, Malac. Brit., xxx, or the Langoustt commune of the French, is sometimes half a metre in length, and when loaded with ova weighs from twelve to fourteen pounds. The shell is spinous and downy, with two stout teeth notched beneath, be- fore the eyes. The superior surface of the body is of a greenish or reddish brown; the tail is spotted and dotted with yellowish, and its segments are marked by a transvei'se sulcus interrupted in the middle, its lateral edges forming a dentatcd angle. The feet are picked in with red and yellowish. It inhabits the coasts of France, that of the Mediterranean in particular. It is found fossil in Italy(l). The third section, that of the Astacini, Latr., is distinguished from the preceding by the form of the two anterior feet, and fre- quently by that of the two following pairs, which terminate in a forceps with two blades, or a didactyle hand. In some, the last two, or four, are much smaller than those which precede them, therein approaching the Anomala; but the fan-like fin of the extremity of their tail and other characters remove them from that section. The thorax is narrow anteriorly, and the front projects in a pointed snout or rostrum. Some of them, — Galaihadeae, Leach, as well as the preceding Ma- croura, have four pairs of false feet; the mediate antennae flexed like (1) M. Desmarest, Hist. Nat. des Crust. Foss., p. 132, speaks of two other fossil species, the second of which, however, may probably belong to the subgenus As- taceus properly so called, and approacli the Jl. nonvegicus of Fabricius. For the other living species, see Ann. du Mus. d'Hist. Nat., t. Ill, p. 391,etseq. ; the article Palinure, Encyc. Method., and its Atlas d'Hist. Nat.; that of Langouste, Nouv. Diet. d'Hist. Nat., Ed. H, and the same in the work of Desmarest on the Crustacea. As respects the nervous system of the species that inhabits the French coast, see Audouln and Edwards, op. cit.; according to them, all the thoracic gan- glions are as if soldered together, end to end. DECAPODA. 63 an elbow, with the two filaments representing the stem, are mani- festly shorter than their peduncle. That of the lateral antennae is never provided with a lamina in the form of a scale. The two ante- rior feet alone terminate in a didactyle hand, which is frequently much flattened. The last segment of the tail is bilobate, at least in most of them. At the head of this division come those whose(l) posterior feet are much smaller and thinner than the preceding onesj they are fili- form, bent up, and useless in locomotion. In the Galathea, Fab. The tail is extended, the thorax nearly ovoid or oblong, the medi- ate antennae salient, and the forceps elongated. The superior sur- face of the body is usually deeply incised or striate, spinous and ci- liate. The most remarkable species of the European seas are the Galaihea rugosa,Fa,h.; Leo, Rondel., Hist. des. Poiss., p. 390; Penn. Brit. Zool., IV, xiii; Leach, Malac. Brit., XXIX, the claws of which are long and cylindrical, the mandibles eden- tate, and that has three long spines in the middle of the front, directed forwards, and ten similar and equally projecting ones on the tail, six on the second segment, and four on the follow- ing one(2). Galathea strigosa; Cancer strigosus, L,, Herbst., XXVI, 2j Pennt. Brit. Zool. IV, xiv| Leach, Malac. Brit., XXVIII, B. Similar, as respects the mandibles, to the preceding species, but having a projection in front, or a rostrum, with four teeth on each side, and an eighth at the end^ the claws are large, but neither very long nor linear, and very spinous, as is a great part of the following feet. This last character distinguishes it from a third species, also found in European seas, the Gatalhea squamifera, Leach., Malac. Brit., XXVIII, B. This learned entomologist has made a peculiar genus, Grimotea, of the Galathea gregaria of Fabricius. The second joint of the in- termediate antennae terminates in a club, and the three last external foot-jaws are foliaceous. It is of a red colour, and was discovered by Sir Joseph Banks in his voyage round the world. It collected in such (IJ According- to a verbal communication from Doctoi- Leach, in the Gaalthea ampledens, Fab., it is not only the two posterior feet which are smaller, but the penultimate likewise. Tiiis species would then form a separate g-enus. (2) This species forms the genus Munida, Leach. See Desmar., Consider., page 191. The latter is mistaken however in attributing to the former the credit of having been the first to discover the identity of this species with the lion of llon- delet. See my Hist. Gener. des Crust, et des Insectes., t. VI, p. 198. 64 CRUSTACEA. immense numbers that the Ocean seemed to be of one blood-red colour. The ,Mglea, Id., is only distinguished from the preceding genus, and from Galathea, by the dentation of the mandibles, by the second joint of the external foot-jaws being shorter than the first, and by the surface of the body being generally smooth(l). That which Risso first named Calypso, and subsequently Janira, in the opinion of Desmarest, — Consider., p. 192, does not diffeF from Galathea. PoRCELLANA, Lam. The Porcellanse form a singular exception among the Macroura, with respect to their tail, which is doubled under as in the Brach- yura. They are otherwise removed from the Galatheae by the more abbreviated, suborbicular, or almost square form of their thorax; by the mediate antennae, which are sunk in their fossulse, by their tri- angular forceps; and finally, by the internal dilatation of the inferior joints of their external foot-jaws. Their body is very flat. They are small, slowly-moving Crustacea, found in every sea, which conceal themselves under stones near the shore. Doctor Leach has formed a genus with certain species — hexapus Latr.j — longicornis. Id., — Blutelij Risso, Crust., I, 7, 8cc., which he calls PisiDiA. According to Desmarest, however, it does not differ in any appreciable character. Some of them are remarkable for their extremely large and pilose or ciliated forceps. Such are, 1. The Porcellane larges pinces; Can- cer platycheles, Penn., Brit. Zool., IV, vi, 12; Herbst., XLVII, 2, where only the external margin of the forceps is pilose and the nearly naked thorax is rounded ; it is found on the rocks in the seas of Europe. 2. The P. hirta, Lam., the whole superior surface of whose forceps and thorax is pilose, and where the latter is nearly oval and becomes thinner anteriorly. It was brought from King's Island by Messrs Peron and Lesueur. The forceps of the others are glabrous. Such is the Cancer hex- apus, L. ; Herbst. XLVII, 4. The thorax is marked with short, transverse, and slightly ciliated lines; the front trifid, with its mid- dle tooth finely notched. The claws are covered with little blood- red scales and granules, the fingers separated and without internal dentations. It inhabits European seas(2). (1) MgUe lisse. Desman, Consider., xxxiii, 2; Latr., Encyclop. Method., All., d'Hist. Nat. cccviii, 2. (2) See the article Porcellane, Nouv. Diet. d'Hist. Nat., Ed., II; and Desmar., Consid., SUP les Crust., p. 192—199. DECAPODA. 65 The genus Monolepis, Say, — Journ. of the Acad, of Nat. Sc. of Philad., I, 155; Desmar., Consid., p. 199 and 200, appears to con- stitute the passage from the Porcellanas to the Megalopes. It ap- proaches the first in the two posterior feet, and in the direction of the tail. But this tail has but six segments, and the eyes are very large as in the second. It would also appear that the lateral fins of the end of the tail resemble those of the latter. The remaining Crustacea of the same division differ from the pre- ceding in their posterior feet, which are similar to their preceding ones in form, proportion and uses, or equally ambulatory. They are also removed from them by the greater thickness and height of the body, the shortness of the lateral antennae, the smallness of the claws, the large eyes, and lateral fins of the tail which are composed of a single lamina. This tail is extended, narrow, and simply bent under near its extremity. Megalopus, Leach. — Macropa, Latr., Encyc. Four species are known, three of which inhabit European seas and the fourth the Indian Ocean(l) whence it was sent to Paris by the late M. Leschenault and Messrs Quoy and Gaymard. In our second division of the Astacini, Latr., will be comprised those which have five pairs of false feet, the mediate antennae straight or nearly so, salient, projecting, and terminated by two fila- ments as long as their peduncle, or longer; and which, a single sub- genus excepted — Gebia — have the four or six anterior feet terminated by a didactyle hand. Their tail is always extended; their two posterior feet are never more slender than the preceding ones, nor folded. The peduncle of the lateral antennae is frequently accompanied by a scale. Some of them, as well as others of the ensuing section, inhabit fresh water. Those in which the first four feet, at most, terminate in two fin- gers; whose lateral antennae never have a scale at the base; and where the external leaflet of the lateral fins of the end of the tail presents no transverse suture, will form a first subdivision. Most of their feet are ciliated or pilose. They inhabit salt-water and con- ceal themselves in holes which they excavate in the sand. Sometimes the index or immovable finger — formed by a projec- tion of the penultimate joint, of the claws, is very evidently shorter (1) For the European species, sec Desmar, Consid., p. 200 — 202, and pi. xxxiv, 2, of the same work. Vol. III.— 1 66 CRUSTACEA. than the thumb or movable finger, merely constituting a simple tooth. The Gebia, Leach, Approaches the preceding sub-genera in the two anterior feet which are alone didactyle. The leaflets of the lateral fins of the end of the tail widen from the base to their extremity, and are marked with longitudinal ridges. The intermediate piece or the last seg- ment of the tail is nearly square(l). Thalassina, Lat. The four anterior feet terminated by two fingers; leaflets of the lateral fins of the end of the tail, narrow, elongated, and without ridges; the last caudal segment or intermediate portion forming an elongated triangle(2). Sometimes the four anterior feet, or the two first and one of the second(3) arc terminated by two elongated fingers, forming a com- plete forceps. The two anterior claws are the largest; the lateral leaflets of the fin terminating the tail, are in the form of a reversed triangle, or widest at the posterior margin; the intermediary, on the contrary, is narrowed from base to apex, and terminates in a point. Callianassa, Leach. The claws of the Callianassse are very unequal, both as to form and proportion; the carpus of the largest of the two anterior ones is transversal, and forms a common body with the forceps; the same joint of the other claw is elongated; the two posterior feet are almost didactyle. The external leaflet of the lateral fins at the end of the tail is larger than the internal, and has a ridge; the latter is smooth. The ocular pedicles are squamiform, and the cornea is situated near the middle of their external margin. The filaments of the me- diate antennae are not longer than their peduncle. Callianassa suhierranea. Leach, Malac. Brit., XXXII, is the only known species. It is found on the coasts of France and Eno-land. The (1^ Thalassina litoraiis, Risso, Crust, III, 2; — Gebia stellata, Leach, Malac. Brit, xxxi, 1 — 9. See Desmar., Consid., p. 203, 204. (2) Thalassina scorpionides, Lat; Career awoma/us, Herbst, LXII; Leach, Zool. Miscel., CXXX; Desmar., Consid, XXXVL (3) The left claw of the second pair seems to be monodactyle in the Callianassse, and the penultimate joint dilated into a palette. DECAPODA. • 67 Axius, Leach, Differs from Callianassa in the claws, which are nearly equal, and in the carpus, which does not form part of the forcepsj the posterior feet are similar to the preceding ones. The leaflets of the lateral fins are nearly equal in size, and have each a longitudinal ridge. The filaments of the mediate antennae are evidently longer than their peduncle. The Jixius stirhynchus, Leach, Malac. Brit., XXXIII, is found on the coast of England, and on that of the western depart- ments of France, where it was observed by M. d'Orbigny, sen., a corresponding member of the Mus. d'Hist. Nat. Our second and last subdivision consists of Crustacea whose six anterior feet form as many claws, terminating in a perfectly didac- tyle forceps, a character which distinguishes them from all the pre- ceding Decapoda, and one which approximates them to the first of the ensuing section; but here the claws of the third pair are the largest, whereas there, it is the two first, besides which they are much thicker. The peduncle of the lateral antennae is accompanied by a scale or spines. The external leaflet of the lateral fins at the end of the tail, in all the living species, is divided in two by a trans- verse suture(l). In the Eryon, Desmar., All the leaflets of the caudal fin are narrowed at their extremity and terminate in a point; the external one presents no transverse suture. The two filaments of the mediate antennae are very shot-t, and hardly longer than their peduncle. The sides of the shell are deeply emarginated. The forceps of the two anterior claws are narrow and elongated. This subgenus was established by Desmarest on a fossil species, — Eryon Cuvieri, Hist. Nat. des Crust. Foss., X, 4; Consid. XXXIV, 3, found in a lithographic, calcareous stone from Pappenheim and Aichtedt in the margraviate of Anspach. AsTACus, Gronov., Fab. Leaflets of the lateral fins at the end of the tail widened and rounded at their extremity; the external one divided transversely by a suture, and the posterior extremity of the mediate obtifse or (1) This character is common to the following' section, so that by it we might divide the Macroura, the Schizopoda excepted, into two great divisions. 68 CRUSTACEA. rounded. The two filaments of the mediate antennae are much longer than their peduncle. The sides of the shell are entire or not incised. In some, all inhabiting salt water, the last segment of the tail, or that which occupies the middle of the terminal fin, presents no trans- verse suture. • Those whose lateral antennae have a large scale on their peduncle, whose eyes are very large and reniform, and the forceps of whose two anterior claws are narrow, elongated, prismatic, and equal, form the genus Nephrops of Leach, the type of which is the Cancer norwegicus, L.; de Geer, Insect., VII, XXIj Herbst., XXVI, 3; Leach, Malac. Brit., XXVI. The two anterior claws are furnished with dentaCed spines and ridges, and the superior surface of the tail is sculptured. It is found in the seas of the north of Europe and in the Mediterranean. Those in which the peduncle of the lateral antennae presents no- thing but two short projections in the form of teeth or spines, whose eyes are neither large nor reniform, and whose forceps are more or less oval, compose, with the fresh water species, the genus Astacus^ properly so called, of the same author. Astacus marimis, Fab.; Cancer gammarus, L.; Herbst., XXV; Penn.,Brit. Zool., V,x, 21; (the Common Lobster). The point or rostrum of the anterior extremity of the shell has three teeth on each side, and another double one at its base. The an- terior claws are very large and unequal; the largest finger of the forceps is oval, with great molar teeth, the other is elongated, and has numerous small ones. Old individuals are sometimes more than half a metre in length. Its flesh is highly esteemed. It is found in the European Ocean, in the Mediterranean, and even on the eastern coasts of North America. Its iliternal structure has been carefully studied by Messrs Victor Andouin, and Milne Edwards. In the fresh water species, which otherwise resemble the preced- ing in their antennae, eyes, and form of the claws, the last segment of the tail, or the middle one of its terminal fin, is transversely di- vided by a suture. The Jistacus communis; Cancer astacus,h.; Roesel, Insect., HI, liv, vii. The Craw-Fish has its anterior forceps granulated, and the inner edges finely dentated. There is a tooth on each side of the snout, and two at its base; the lateral edges of the seg- ments of the tail form an acute angle. Its colour, which is usually a greenish brown, is sometimes altered by accidental circumstances. This species, which inhabits the fresh waters of Europe, has been more particularly studied, both as respects its anatomy DECAPODA. 69 and habits, and the faculty enjoyed by the Crustacea of regene- rating their antense and feet when they are either mutilated or destroyed. When about to cast its shell, two stony concretions are found in the stomach, formerly much used in medical prac- tice as an absorbent, but now replaced by the carbonate of mag- nesia. It conceals itself in holes, or under stones, never quitting its retreat except to search for food, which consists of small Mollusca and Fishes, and the larvse of Insects. It also feeds on putrid flesh, the carcases of quadrupeds, for instance, which are placed as a bait for them in nets, or in the centre of fagots of wood. They are also taken in their holes by the light of torches. It changes its shell towards the end of spring. Two months after coition, which takes place ventribus junctis, the female produces her ova, which are at first collected in masses, and glued to the false feet by means of a viscid humour. They are of a reddish brown colour, and enlarge before they are hatched. The young Astaci, at first extremely soft and precisely like their parent, shelter themselves under her tail and remain there several days, until their bodies acquire a certain degree of solidity. The term of existence assigned to the Astaci seems to be twenty years and upwards, their size augmenting in proportion to their age. Those are preferred for the table which inhabit running streams of fresh water. A parasitic animal belonging to the Annelides, is found on their branchiae, long ago observed by Roesel, but imperfectly known until the researches of M. Odier(l). The fresh-waters of North America produce another species, the A. Bartonii, figured by Bosc. — Hist. Nat. des Crust., II, x, 1. A third inhabits the rice-fields of the same country, to which, according to Major Le Conte, one of the best naturalists of the United States, it is very injurious. In the fourth section, that of the Carides, the intermedial anten- nas are superior or are inserted above the laterals: the peduncle of these latter is completely covered by a large scale. 'i'heir body is arcuated, almost gibbous, and of a less solid con sistence than that of the preceding Crustacea. The front is always drawn out into a point, and most frequently so as to resemble a ros- trum or pointed lamina compressed and dentated along the edges. (1) See his ^Memoire sur le Branchiodelle, inserted in the Mem. de la Soc. d'Hist. Nat. tome I, p. 69, et seq. 70 CRUSTACEA. The antennae always project; the laterals are usually very long and resemble very fine setae ; the intermediaries of a great number ter- minate in three threads. The eyes are closely approximated. The external foot-jaws, more elongated and narrow than usual, resemble palpi or antennx. The mandibles of most of them are compressed and arcuated at the extremity. One of the first pairs of feet is fre- quently flexed upon itself. The segments of the tail are dilated or widened laterally. The external leaflet of its terminal fin is always divided in two by a suture, a character observed nowhere else ex- cept in the last Crustacea of the preceding section; the azygous por- tion of the middle, or the seventh and last segment is elongated, narrowed near the extremity and provided above with ranges of small spines. The false feet, of which there are five pairs, are elon- gated and usually foliaceous. Immense numbers of these Crustacea are consumed in all parts of the world. Some species are even salted in order to preserve them. In some of them, the three first pairs of feet form a didactyle claw, the length of which progressively augments, so that the third pair is the longest. Such are the Pex^us, Fab., Where there is no annular division in any of the joints of the feet. Their mandibular palpi are turned up and foliaceous. A little elliptical appendage may be seen at the base of the feet, a character which seems to approximate them to Pasiphaea, the last genus of this section, and to those of the following one. Some, all indigenous to Europe, on account of the shortness of the two threads of their intermediate antennae, form a first division. It contains the following species. P. sulcatus; Palxmon sulcafits, Oliv., Encyclop.; Caramote, Rond., Hist. Nat. des Poiss., liv. xviii, chap. 7. Nine inches long; on the middle of the thorax a longitudinal carina bifurcated at base, terminated by a projecting rostrum, compressed, with eleven teeth in its upper edge and one in the lower; a longitu- dinal sulcus along each side of the carina. This species is very common in the Mediterranean and the object of considerable commerce. It is salted and shipped to the Levant. The P. trisulcatus, Leach, Malac. Brit. XLII, which inhabits the coast of England, is perhaps a mere local variety of the sulcatus. Its thorax is trisulcate and the ros- trum bidentate beneath. In the P. d'Orbigny, — Lat, Nouv. Diet. d'Hist. Nat., Ed. II, article Penee, the carina is not sulcated. DECAPODA. 71 The intermediate antennae of others are terminated by long threads^ they constitute our second division to which we refer. Fenxus monodon. Fab.; Squilla indica, Bont., Hist. Nat., p, 81, which inhabits the Indian Ocean. F. antennatus, Risso, Crust., II, 6, and F. mars, Id., II, 5, also appear to belong to it. Stenopus, Lat. Distinguished from the Pensei by the transverse and annular di- visions of the two penultimate joints of the four posterior feet. The entire body is soft; the antennae and feet are long and slender, those of the third pair widest. But a single species is known. It was brought from the seas of New Holland by M. Peron and Lesueur. Olivier retains it in the genus Palsemon — Cancer setiferus, L.; F. hispidus, Oliv., Encyclop. and Atl., d'Hist. Nat., CCCXIX, 2; Seba, Mus., Ill, « XXI, 6, 7; Herbst., XXXI, 3, where I first placed it. The remaining Carides, the intermediate antennse of many of which are terminated by three threads, have at most but two pairs of didactyle claws formed by the four anterior feet. A subgenus founded on a single species peculiar to North Ame- rica, that of Atya,, Leach, Is removed from all analogous Crustacea by an anomalous cha- racter. The forceps terminating the four claws is cleft down to its base, or seems to be composed of two fingers in the form of thongs united at their origin; the preceding joint is crescent-shaped. The second pair is the largest. The intermediate antennas have but two threads. In all the following subgenera, the blades of the forceps originate at a certain distance from the base of the penultimate article, or of that which has the form of a hand; the body or the part that pre- cedes it is not lunulated. We now have in the first instance those Carides whose feet are generally robust and not filiform, and which have no appendage to their external base. Their body is neither very soft nor greatly elongated. Among these subgenera, whose feet are deprived of this appen- dage, the three following present an insulated form with respect to their claws. Crangon, Fab. The two anterior claws, which are larger than the subsequent feet,^ 72 CRUSTACEA. have but a single tooth in place of the index or immovable finger, and that which is movable is bent and hooked. The superior or intermediate antennae have but two threads. The second feet are folded up, and are more or less distinctly bifid or didactyle at their extremityj neither of the joints is annulated. The rostrum is very short. We do not separate the Egeon, Risso, or the Pontophilus, Leach, from Crangon. In the former, the last joint of the external foot- jaws is twice the length of the preceding one, while in the latter they are equal. The second feet of the Egeones are shorter than the third and the smallest of the whole number, whilst in Crangon their length is the same. Besides, as the number of species is very limited, this generic distinction becomes the less necessary. C. vulgaris. Fab.; Rccs., Insect., Ill, Ixiii, 1,2. (The Shrimp), about two inches long. It is smooth, of a pale glaucous green, dotted with grey. That part of the thorax which supports the third pair of feet, projects in a point. This species is very com- mon on the oceanic coast of France, where it is vulgarly called the Cardon. It is taken there annually in nets. Its flesh is deli- cate, and highly esteemed. In the same locality, though rarely, according to M. Brcbisson, is found the C ponctue de rouge, of Risso; but I consider it, with him, as a mere variety. The C. loricatus — Egeon loricatus, Rissoj Cancer cataphractus, Oliv., Zool., Adriat., Ill, 1, has three longitudinal and dentated ridges on the thorax. Northern seas produce a large species, the Crangon boreas, Phipps., Voy. to the North Pole, pi. xi, 1, Herbst. XXIX, 2. Processa, Leach. — Nika, Risso. One of the two anterior feet simply terminating in a point, the other in a didactyle claw; the two following are unequal, slender, and also didactyle. One of these second feet is very long, its carpus and the preceding joint being annulated, a character which on the other foot is only found in the first of these joints. The fourth pair of feet are longer than the preceding and two following ones. The superior antennae have but two threads. P. edulis; Nika edulis, Riss., Crust., Ill, 3, is of a flesh colour dotted with yellowish; a line of small yellow spots in the middle. The anterior extremity of the shell is furnished with three sharp points, the intermediate of which, or the rostrum, is the longest. The two anterior feet are equal in size, the right one forming a forceps. This species is found during the whole year DECAPODA, 73 in the markets at Nice. It is also found on the coast of the department of France, called the Bouches-du-Rh6ne(l). Hymenocera, Latr. The two anterior feet terminated by a long hook with a bifid ex- tremity, and composed of very short divisions. The two following are very largej the hands, immovable finger, and superior thread of the intermediate antennae are dilated, membranous, and almost foli- aceous. The external foot-jaws are equally foliaceous, and cover the mouth. The only species known is in the collection of the Museum d'Histoire Naturelle, and was captured in the Indian Ocean. We now pass to subgenera, in which the claws present no remark- able or insulated peculiarity. Sometimes the superior or intermediate antennae are only termi- nated by two threads. The rostrum is usually short. Gnathophyllum, Latr. The Gnathophylla are the only ones which approach the Hyme- nocerae in the size of their foot-jaws. The four anterior feet form di- dactyle claws; the second pair is longer and thicker than the first. Neither of the segments of the four is annulated(2). PoNTONiA, Latr. The four anterior feet, as in the two following subgenera, didac- tyle claws, but the carpus is not annulated(3). Alpheus, Fab. The four anterior feet also terminated byadidactyle claw, but the carpus of the second is articulated. The latter are shorter than the former(4). (1) For the remaining species, see Risso, Hist. Nat. des Crust, de Nice; Leach, Make. IJrit., XLI; and the Nouv. Diet. d'Hist. Nat., Ed. 11. (2) Alpheus elegans, Risso, Crust., II, 4; Desmar., Consid., p. 228. (3) Alpheus thyrenus, Risso, Crust., II, 2; Astacus thyrenus, Fetag., V, 5; Des- mar., lb., p. 229. (4) Alpheus malabaricus. Fab., and probably some other species, with which, however, I am not sufficiently acquainted. See Desmar., Consid., p. 222, 223. Vol. III.-K 74 CRUSTACEA. Hyppolyte, Leach. The Hyppolytes only difTer from Alpheus in the respective pro- portion of their claws; the second are longer than the first(l). The two last followinp; subgenera have this peculiarity; but a sin- gle pair of their feet terminate in a didactyle claw. In the AUTOXOMEA, RissOj It is the two anterior, which are also distinguished frona the others by their size, their thickness, and their disproportion(2). In Paxdalus, Leach, The two anterior feet are simple, or hardly bifid; the two following ones are longer, of unequal length and didactyle, the carpus and preceding segment annulated. The external foot-jaws are very long and slender, at least in some of them. The anterior projection of the shell is greatly extended, and multidentate(3). Sometimes the superior antennse have three threads. They have four didactyle claws, the smallest of which are folded up, and an elongated rostrum. PALiEMON, Fab. Prawns are distinguished from the two following subgenera by their inarliculated carpus; the second feet are larger than the first; the latter are doubled up. A remarkably large species is found in the East Indies, the second claws of which are very long. Tolerably large ones are also found at the Antilles, some of which frequent the mouths of rivers. Those on the coast of France are much smaller, and are known there by the vulgar names of Crevettbs and Salicoques. Their flesh is more highly esteemed than that of the Shrimp. Ac- cording to ]M. de Brebisson— Catal. Method, des Crust, terrest. et fluviat., de depart, du Calvados, — they are taken in the same manner as tlie latter Crustacea, but in the summer only. Prawns swim well, particularly when escaping from pursuit, and in various directions. They are always found about the shore. The lithographic stone of (1) To this subgenus should be referred the Palaemon diversimane, and F. marhrc, of Olivier. See Desmar., Consid., p. 220. (2) Autonomea Olivii, Risso, Crust., p. 166; Cancer glaber, Oliv., Zool. Adriat., Ill, 4; Desmar., Consid., p. 251, and 252. (o) Pundalus annuUcomis, Leach, Malac. Brit., XL; Pandalus narwal, Latr.; Jhtacus narwal. Fab.; Falwmoti pristis, R'uso; Cancer armiger? Herbst., XXXIV, 4. See Desmar., Consid., p. 219, 220. DECAPODA. 75 Pappenheim and Solhnofen, frequently exhibits the debris of a fossil crustaceous animal, referred by Desmarest to the Prawns, under the specific appellation of spinipes — Hist. Nat. des Crust. Foss. XI, 4. It does in fact resemble it, but the claws are wanting. A second fossil species, but much larger, has been discovered in England. Pal. serrntus, Leach, Malac. Brit. XLIII, 1, \0; Herbst., XXVII, I, is from four to five inches long, of a pale red colour, •which becomes more vivid on the antennic, the posterior mar- gin of the segments of the tail, and particularly on the terminal fin. The rostrum extends beyond the peduncle of the interme- diate antennae, is recurved at its extremity, and has five teeth above, exclusive of the point, and five beneath. The fingers are as long as the penultimate joint. It is found on the coast of France and England, and is the species of this subgenus that is more particularly sold at Paris. A sort of wen is frequently, and at all seasons, observed on one side of the shell, which co- vers a parasite Bopyrus, which fastens upon its branchiae. Fed. squilla. Leach, Malac. Brit., XLIII, II — I3j Cancer squilla, L.; Squilla fusca, Bast., Opusc. subs., lib. 2, 111, 5, is but half the size of the serra.tus. • Its rostrum scarcely extends beyond the peduncle of the superior antennae, is almost straight, or but slightly recurved, is emarginated at the extremity, and has seven or eight teeth above, and three below. The fingers of the claws are somewhat longer than the hand. 'Common on the coast of France and England(l). The carpus is articulated, or presents annular divisions in the two following genera, viz. Sysmata, Risso: ante Melicerta, ejusd. Where the second pair of claws are larger than the first(2), and Athanas, Leach, In which, on the contrary, the first pair is larger than the se- cond(3). The last subgenus of this section, that of (1) See the article Palemon, Encyclop. Method., and of the second edition of the Nouv. Diet. d'Hist. Nat., and Desmar., Consid-, p. 236 — 238. See also in re- lation to the nervous system, the Mem. Cit., of Messrs Audouin and Milne Ed- wards. (2) Lysmata seticauda, Risso, Crust., II, 1; Desmar., Consid., p. 238. (3) Mhanas nitescms. Leach, Malac. Brit., XLIV; Desmar., Consid., p. 239, 240; de lireb., Crust, du Calv., p. 23, 24. 76 CRUSTACEA. PasiphjEA, Sav., Although closely approximated to several of the preceding by the superior antennae which are terminated by two threads; by the form of the four anterior feet, terminating in a didactyle forceps, and pre- ceded by a joint, without annular divisions, and by the shortness of the rostrum, differs from them in several respects. A testaceous ap- pendage is very evident at the external base of their feet; these'lat- ter, with the exception of the claws, which are larger and nearly equal, are very slender and filiform; the body is greatly elongated, strongly compressed, and extremely soft. Pas. sivado; Alpheus sivado, Risso, Crust., Ill, 2; Desmar., Consid., p. 240, is two inches and a half long, and four lines and a half in breadth. The body is transparent, of a nacre white edged with red, the caudal fin marked with small dots of the same colour. The rostrum is sharp and slightly curved at the point. Claws reddish. It is very abundant on the shores of Nice, and according to Risso spawns in June and July. No other species has yet been observed. Our fifth and last section of the Macroura, that of the Schizopoda, appears to connect the Macroura with the following order. The feet, none of which terminates in a forceps, are very slender, resem- ble thongs, are furnished with an appendage more or less long, aris- ing from their external side near their base, and serving for nata- tion only. The ova are situated between them, and not under the tail. The ocular pedicles are very short. As in most of the Ma- croura the front projects into a point or rostrum. The shell is thin, and the tail terminates, as usual, in a sort of fin. They are small, and inhabit salt water. Here the eyes are very apparent; the lateral antennae are accom- panied by a scale, and the intermediaries terminated by two threads and composed of several small segments, as in the preceding genera. Mysisj Latr. Antennae and feet exposed; the shell elongated; nearly square or cylindrical; the eyes closely approximated, and the feet capillary, as if formed of two threads(l). (1) Mysis Fahricii, Leach; Encyc. Method., Atl., d'Hist. Nat., CCCXXXVI, 8, 9; Cancer oculatus, 0th.; Fab., Groenl., fig. 1. See Desmar., Gonsid., p. 241, 242. DECAPODA.. 77 Cryptopus, Latr. A subovoid inflated shell, curving downwards on the sides, enve- loping the body as well as the antennae and feet, exhibiting beneath a mere longitudinal fissure. The eyes are separated, and the feet in the form of thongs, with a lateral appendage(l). There the eyes are concealed; the intermediate antennae are coni- cal, inarticulated, and very short; the laterals are composed of a peduncle, and a thread without any distinct articulations. There is no — at least salient — scale at their base. Such is the MuLcioN, Latr. The body is soft and thorax ovoid. The' feet are in the form of a thong, and most of them have an appendage at their base; the fourth pair is the longest. I know but one species, the Mulcion Lesueurii, which was captured by that zealous naturalist in the seas of North Ame- rica. The late Olivier, in the Pinna marina, found a crusta- ceous animal very similar at the first coup d'oeil to the Lesueu- rii, but the specimens -were so much injured that it is impossible for me to study their characters. The Nebaliae, which Ave at first placed in this section, having no natatory appendages under the last segments of their body, and their feet being tolerably similar to those of a Cyclops, will pass with the Condylura into the order of the Branchiopoda, at the head of which they will stand. The Nebalias, by their very prominent eyes, which seem to be on pedicles, and by some other characters, appear to connect the Schizopoda with the Branchiopoda. ORDER 11. STOMAPODA. The branchiae of the Stomapoda are exposed and at- tached to the five pairs of sub-abdominal appendages, exhi- bited to us by that part of the body, called tail, in the De- capoda, and which here, as in most of the Macroura, are fitted (1) Cryptopus Defrancii, Latr., from the Mediterranean. 78 CRUSTACEA. for natation, or are fin-feet. Their shell is divided into two portions, the anterior of which supports the eyes and in- termediate antennaB, or composes the head, without giving origin to the foot-jaws. These organs, as vyell as the four anterior feet, are frequently approximated to the mouth ou two lines that converge inferiorly, and hence the denomina- tion of Stomapoda aflixed to this order. Judging hy the Squillse, the most remarkable genus of this order, and the only one hitherto studied, the heart is elongated, and similar to a large vessel. It extends along the whole length of the back, rests upon the liver and intestinal canal, and terminates poste- riorly and near the anus, in a point. Its parietes are thin, transparent, and almost membranous. From its anterior ex- tremity, placed immediately beliind the stomach, arise three principal arteries, the mediate of which — the ophthalmic — giving off several branches on each side, is more particularly directed to the eyes and intermediate antennae, and the two lateral ones — the antennaries — pass over the sides of the sto- mach and are lost in the muscles of the mouth and of the ex- ternal antenniE. No artery arises from the superior surface of the heart, but a great many issue from its two sides, each pair of which, as it appears to us, corresponds to a particular segment of the body, commencing with the foot-jaws, whether these segments be external, or concealed by the shell, and even very small as is the case with those that are anterior. On a level with the first five abdominal annuli, or those to which the natatory appendages and the branchiae are attached, this superior surface of the heart receives, near the median line, five pairs of vessels — a pair to each segment — proceeding from these latter organs, and which, according to Messrs Audouin and Milne Edwards, are analogous to the branchio- cardiacs of the Decapoda. A central canal (1 ) situated under (1) See our general observations on the Macroura. Neither this vessel nor the venous sinuses have been observed in the subsequent orders; but the heart pre- serves the same elongated form, and presents similar anterior arteries. From its sides also arise other arteries corresponding to the articulations of the body. In addition to the pre-cited Memoir, see the Lejons d'Anatomie Comparee of the Baron Cuvier. STOMAPODA. 79 the liver and intestine receives the venous blood which is poured into it from all parts of the body. On the level of each segment to which the foot-jaws and branchiae are attach- ed, it gives off a branch on each side, running to that part of tlie branchisB which is situated at the base of the correspond- ing foot-jaw. The parietes of these vessels appear to the above mentioned gentlemen to be smooth and continuous, but formed by a layer of lamellated cellular tissue glued to the neighbouring muscles, rather than by a membrane proper; these vessels also appeared to them to communicate with each other near the lateral margin of the annuli, but they could not positively affirm it. The afferent or internal vessels of the branchiae, which in these Squillse form tufted bunches, are continuous with the branchio- cardiac canals, are no longer lodged in cells, pass between muscles, turn obliquely over the lateral part of the abdomen, reach the anterior margin of the preceding ring, and terminate on the superior surface of the heart near the median line, one partly mounting on the other. The medullary cord, exclusive of the brain, presents but ten ganglions, of which the anterior furnishes nerves to the mouth, the three following, those of the six natatory feet, and the last six, those of the tail. Thus, although the four last foot-jaws represent the four anterior feet of the Decapoda, they never- theless form a part of the organs of raanducation. The sto- mach of these Crustacea — Sq'uillae — is small and has but a few very small teeth(l) near the pylorus. It is followed by a straight and slender intestine which extends along the whole abdomen, accompanied on the right and left by glandular lobes which appear to supply the want of a liver. A ramous ap- pendage adhering to the inner base of the last pair of feet appears to characterize the male. The teguments of the Stomapoda are thin, and in several, nearly membranous or diaphanous. The shell is sometimes formed of two shields, of wliich the anterior corresponds to the head and the posterior to the thorax, and sometimes of (1) They form two ranges of transverse and parallel striae. 80 CRUSTACEA. a single piece, which however is free behind, usually exposing the thoracic segments, bearing the three last pairs of feet and having an articulation before that serves as a base to the eyes and intermediate antennae ; these latter organs are always ex- tended and terminated by two or three threads. The eyes are always approximated. The formation of the mouth is essentially the same as in the Decapoda ; but the palpi of the mandibles, instead of being laid on them, are always vertical. The foot-jaws are deprived of the ilagelliform appendage pre- sented to us by the same parts in the Decapoda. They have the form of claws or of small feet, and, at least in several — the Squiilai, — their external "base as well as that of the two anterior feet properly so called, exhibits a vesicular body. Those of the second pair, in the same Stomapoda, are much larger than the others and even than the feet, which has caused them to be considered as true feet ; fourteen of them have been counted(l). The four anterior feet have also the form of claws, but are terminated as well as the foot-jaws by a hook which curves towards tlie head, on the inferior and ante- rior edge of the preceding joint or of the hand. In others how- ever — the Phyllosoma for instance(2) — all these organs are filiform and have no forceps. Some of them at least, as well as the last six and equally simple ones of the Stomapoda pro- vided with claws, have an appendage or lateral branch. The seven last segments of the body,' containing a large portion of the heart and furnishing a base for the attachment of the res- piratory organs, can no longer in this respect be assimilated to that portion of the body which is called the tail in the De- capoda : it is a true abdomen. Its penultimate segment has a fin on each side formed like the caudal of the Macroura, but is frequently, as well as the last segment or intermediate portion, armed with spines or teeth. (1) The second jaws of these Stomapoda no longer present the same form as those of the Decapoda. They have the figure of an elongated triangle divided into four segments by transverse lines. The mandibles are bifurcated and well dentated. (2) In all those where the four anterior feet are in the form of claws, the six last are natatory. STOMA POD A. 81 The Stomapoda are all marine Crustacea. Their favourite habitat is in the intertropical latitudes, and they are not found beyond the temperate zones. Of their habits we are totally ignorant ; that those which are furnished with claws use them in seizing, their prey, in the manner of those Orthoptera called in Provence Pregadious or Mantes{\), we cannot doubt. Hence their vulgar appellation of Sea- Mantis: they are the Crangones and Crangines of the Greeks. According to Risso they prefer sandy bottoms in deep water, and copu- late in the spring. Other Stomapoda, those of our second family, being less favoured with natatory appendages and having a much flatter and more superficially extended body, are generally found on the surface of the water, where they move very slowly. We will divide the Stomapoda into two families. FAMILY I. UNIPELTATA. In this family the shell consists of a single shield, of an elongated quadrilateral form, usually widened and free behind, covering the head, the antenna and eyes excepted which are placed on a common anterior articulation, and at least the first segments of the body. Its anterior extremity terminates in a point or is preceded by a small plate with a similar end. All the foot-jaws, the second of which are very large, and the four anterior feet are closely approximated to the mouth on two inferiorly converging lines, and have the form of claws with a single finger or mobile and flexed hook. With the exception of the second feet all these organs are furnished at their external origin with a little pediculated vesicle. The other six feet, at the base of whose third segment is a lateral appendage, are linear, terminated by a brush, and simply na- (1) Some othei" analot^ous Orthoptera, such as the Phyllium, resemble leaves. The I'hyllosomse, Crustacea of the same order, exhibit similar affinities. Vol. III.— L 82 CRUSTACEA. tatory. The lateral antennae have a scale at their base^ and the stem of the intermediaries is composed of three filaments. The body is narrow and elongated ; the ocular pedicles are always short. This family is composed of but one genus, that of Squilla, Fab., Which we will divide in the ioUowing manner: In some the crustaceous shield is preceded by a small and more or less triangular plate, situated above the segment in which the eyes and mediate antennae are inserted, only covers the anterior por- tion of the thorax, and does not curve downwards on the sides. The piece which serves as a peduncle to the mediate antennss, as well as the ocular pedicles and the external sides of the end of the abdomen, are exposed. Here the body is almost semi-cylindrical, the posterior edge of J the last segment being rounded, dentated or spinous; the lateral ap- i pendages of the last six feet are styliform. SquiLLA, Lat. The true Squillse, along the whole inner side of the penultimate segment of the two large claws, have an extremely narrow groove, dentated on one of its edges and spinous on the other, and the ensu- ing joint or the claw, falciform and usually dentated. Squilla mantis; Cancer mantis, L..; Herbst., XXXIII, 1; En- cyclop. Method., Atl. d'Hist. Nat., CCCXXIV; Desmar., Con- sid., XLI, 2, is about seven inches in length. The base of the large forceps is furnished with three movable spines, and its claws have six elongated and sharp-edged teeth, the last one being the largest. The segments of the body, the last one ex- cepted, are marked by six longitudinal ridges, mostly termi- nating in a sharp point; the middle of the last is strongly cari- nated, punctured and terminated posteriorly by a double range of indentations, and four very stout points, the mediate teeth of which are most closely approximated; each lateral margin has two reflected or thicker divisions, the last one terminating in a point. The peduncle of the lateral fins is prolonged beneath and terminated by two very strong teeth. It is common in the Mediterranean. The Squille de Desmarest, Rlsso, Crust. II, 8, which also inhabits the same sea, is but two inches and a half in length. Its claws have five teeth; the shell and the middle por- STOMAPODA. 83 tion of the abdominal segments, the last ones excepted, are smooth(l). In the GONODACTYI-I'S, Lat., The groove of the penultimate segment of the large claws is wi- dened at its extremity, presenting neither dentations nor spines. The finger is dilated, or resembles a knot near its base, terminating in a straight or slightly curved compressed point. They are all foreign to Europe(2). There, the body is extremely narrow and depressed, and the last segment almost square, entire, and without dentations or spines. The lateral appendage of its last six feet is in the form of an almost orbicular and slightly bordered palette; the antennae and feet are shorter than in the preceding; the penultimate segment of the large claws has its inner margin fringed with numerous cilia in the form of little spines; the finger is falciform. CoRONis, Latr. But a single species is known(3). In the remaining Stomapoda of this family the shell is almost membranous and diaphanous, covers the Avhole thorax, is curved la- terally beneath, prolonged anteriorly into a spine or ensiform blade, and projects above the base of the mediate antennas and of the eyes. This base or support is susceptible of being curved under and en- closed in the case formed by the curvature of the shield. The pos- terior fins are concealed under the last segment. These very small, soft Crustacea are peculiar to the Atlantic Ocean and the Eastern seas. The fingers of the large claws have no teeth; the second joint of the ocular pedicles is much larger than the first, and has the figure of a reversed cone; the eyes properly so called are large and almost globular; the fin-like appendage of the feet resembles that of the Squillse and Gonodactyli. In the Erichthus, Latr. — Smerdis, Leach, The first joint of the ocular pedicles is much shorter than the second; the middle of the lateral edges of the shield has a strongly (1) For the other species, see the article Squille, and pi., of the Encyc. Method.; Desmar., Consid. In pi. XLII, he has given a detailed figure of the Squille queue-rude. (2) Squilla scyllarus. Fab.; Rumph., Mus., Ill, F; — Squilla chirag7-a, Fab.; Desmar. Consid., XLIII. See the article Squille, of the Encyclopedia Metho- dique. (3) See Encyclop. Method., art. Squille. Squilla eusebia? R\sso. 84 CRUSTACEA. angular dilatation, and their posterior extremity exhibits two tceth(l). In Alima, Leach, The first joint of the ocular pedicles is slender, cylindrical, and much longer than the following one; the body is narrower and more elongated than that of an Erichthus; the lateral borders of the shield are nearly straight or are but slightly dilated; there is a slight longitudinal carina on its middle, and each of its angles forms a spine, the two posterior of which are the largesl(2). FAMILY II. BIPELTATA. In this family we find the shell divided into two shields, the anterior of which, very large and more or less oval, forms the head, and the posterior, corresponding to the thorax, transverse and angular in its circumference, supports the foot- jaws and feet. These latter, with the exception at most of the two posterior and two last foot-jaws, are slender and fili- form, usually very long and accompanied by a lateral, ciliated appendage. The other four foot-jaws are very small and conical. The base of the lateral antennae exhibits no scale ; the intermediaries are terminated by two threads. The ocu- lar pedicles are long. The body is much flattened, mem- branous, and diaphanous ; the abdomen small and its posterior fin without spines. It comprises but a single genus, the Phyllosoma, Leach, Of which all the species inhabit the Atlantic Ocean and Oriental seas(3). (1) Erichthus vitreus, Lat. See art. Squille, Atl. d'Hist. Nat. of tlie Encyclop. M(^thod., pi. cccliv; and Desmar. Consid., XLIV, 2, 3. (2) Alima hyaliiw, Lat., Encyclop. Method., art. Squille, and Ibid. Atl. d'Hist. Nat., CCCLIV, 8; Desmar., Consid., XLIV, ]. (3) See Encyclop. Method., and Nouv. Diet. d'Hist. Nat., Ed. II, article Phyl- losome; also the work of Desmarest on the Crustacea and the Zoology of the Voy. de Freycinet. As respects their nervous system, the Phyllosomae seem to be in- termediate between the preceding- and subsequent Crustacea. See Audouin and Edwards, OD. cit. CRUSTACEA. 85 MALACOSTRACA. h. Eyes sessile and immovable. The Branchiopoda are the only Crustacea of which we shall 'henceforward have occasion to speak, that exhibit eyes placed on pedicles. But independently of the fact that these pedi- cles are neither articulated nor lodged in special cavities, the Branchiopoda have no shell and are otherwise removed from the preceding Crustacea by various characters. All the Ma- lacostraca of this division are also deprived of a shell ; their body, from the head downwards, is composed of a suite of articulations of which each of the first seven is furnished with a pair of feet, the following and last ones, seven at most, forming a sort of tail terminated by fins or styliform appen- dages. The head presents four antennae, the two interme- diate superior, two eyes, and a mouth composed of two man- dibles, a tongue, two pairs of jaws, and a sort of lip formed by two foot-jaws that correspond to the two superior ones of the Decapoda ; here, as in the Stomapoda, the flagrum no longer exists. The four last foot-jaws are transformed into feet, sometimes simple and at others constituting a claw, but almost always with a single toe or hook. According to the observations of Messrs Audouin and Ed- wards, the two ganglionary cords of the spinal marrow are perfectly symmetrical and distinct throughout the whole of their length, and from those of the Baron Cuvier it would ap- pear that the Onisci are only removed from them because these cords do not present the same uniformity in all the seg- ments of the body, and because there are some ganglions less(l). Thus, according to them, the nervous system of the Crustacea is the simplest of all ; in the Cymothoae and Idoteae the two ganglionary chains are no longer distinct, and those (l) See 0N'i!icu3. 86 CRUSTACEA. ganglions which immediately follow the two cephalics, form as many small circular masses situated on the median line of the body; but tlie cords of communication which serve to connect them, remain isolated and attached to each other. It would appear' from these fiicts that the latter Crustacea are higher in the animal scale than the preceding ones, but other considerations seem to us to require a considerable separation between the Talitri and Onisci, and the arrangement of the CymothocT and Idoteai in an intermediate rank. The organs of generation are situated inferiorly near the origin of the tail. The two first appendages with which it is furnished beneath, and which are analogous to those presented to us by the same part in the preceding Crustacea, but more diversified, and always, as it appears, supporting the bran- chiae, differ in this respect, according to the sex. The coitus takes place like that of insects, the male placing himself on the back of his female : the latter carries her ova under the thorax, between scales which form a sort of pouch. There they are developed, and the young remain attached to the feet or other parts of the body of their mother, until they have ac- quired the strength requisite for natation, and providing for their wants. All these Crustacea are small, and mostly in- habit the sea-coast or fresh water. Some are terrestrial, and others are known which are parasitical. They are divided into three orders : those whose mandibles are furnished with a palpus, appear to be naturally connected with the preceding Crustacea — such are the Amphipoda ; those in which these organs are deprived of them will consti- tute the two following orders — the Lsemodipoda and the Iso- poda. The Cyami, a genus of the second one, being parasi- tical, naturally lead ,us to the Bopyri and Cymothoae, with which we commence the Isopoda. AMPHIPODA. 87 ORDER III. AMPHIPODA. The Amphlpoda are the only Malacostraca with sessile and immovable eyes, whose mandibles, like those of the preceding Crustacea, are furnished with a palpus, and the only ones whose subcaudal appendages, always very apparent, by their narrow and elongated form, their articulations, bifur- cations, and other incisures, as well as by the hairs or cilia with which they are provided, resem.ble false or natatory feet. In the Malacostraca of the following orders, these appendages have the form of laminae or scales ; here these hairs and cilia appear to constitute the branchiae. Many of them, like the Stomapoda and the Lsemodipoda, have vesicular bursae either between their feet or at their external base, the use of which is unknown. The first pair of feet, or that which corresponds to the se- cond foot-jaws, is always annexed to a particular segment, the first after the head. The antennse, which, with a single ex- ception — the Phronimse, — are four in number, project, gra- dually taper into a point, and consist, as in the preceding Crustacea, of a peduncle and a single stem, or ©ne furnished at most with a little lateral branch, and usually composed of several joints. The body is generally compressed and curved beneath posteriorly. The terminal appendages of the tail are most frequently styliform and articulated. Most of them swim and leap with facility and always laterally. Some in- habit springs and rivulets, and are often found in couples consisting of the two sexes ; most of them however live in salt water. Their colour is uniform, verging on reddish or green- ish. They may all be comprised in a single genus, that of Gammarus, Fab., Which we may subdivide, in the first place, into three sections, from the form and number of the feet. 88 CRUSTACEA. 1. Those which have fourteen feet all terminated by a hook, or in a point. 2. Those which also have fourteen feet, but which are — the four last at least — simply natatory. 3. Those which have only ten apparent feet. The first section is divided into two. Some of them, — the Uropteua, Latr., usually have a large head; the antennae are frequently short, and in some but two in number; the body is soft. All the feet, the fifth pair at most excepted, are simple, the anterior are short or small, and the tail is either fur- nished at the extremity with lateral fins, or is terminated by points or appendages, widened and bidentated, or forked at their posterior extremity. They inhabit the bodies of various Acephala or Lin- naean Medusse, and of some other Zoophytes. Here, as in Phronima, Lat., There are but two — very short and biarticulated — antennae; the fifth pair of feet is the largest of all and terminates in a didactyle forceps; the six appendages of the extremity of the tail are styli- form, elongated and forked , or bidentated at the end; six vesicu- lar sacs may be observed between the last feet. Several species ap- pear to exist, but they have not been strictly and comparatively de- scribed. That which has been taken for our type is the Cancer seden- tarius, Forsk. , Faun. Arab., p. 95; Latr., Gener. Crust, et In- sect. I, ii, 2,3, which is found in the Mediterranean, and in- habits a membranous transparent body that has the figure of a cask, and which appears to proceed from the body of a species of Beroe. The Phronime sentinelle, Risso, Crust., II, 3, inhabits the in- terior of Med usee, constituting the genera Equoree and Ge'ro- nie of Peron and Lesueur. Another species, according to Leach, has been observed on the coast of Zealand. There we observe four antennae; all the feet are simple; on each side of the extremity of the tail is a lamellated or foliaceous fin, the leaflets of which are acuminated or unidentated at the end. Hyperia, Lat. The body thickest anteriorly; the greater portion of the head oc- cupied by oblong eyes somewhat emarginated on the inner edge; AMP¥1P0DA. 89 two of the antennas, at least half as long as the body and terminated by a long setaceous stem composed of several small joints(l). Phrosine, Risso. Form of the body and that of the head similar to the Hyperiae, but the antennae, at most, the length of the latter, composed of but few and styliform joints, or terminated by a stem resembling an elon- gated cone(2j. Dactylocera, Lat, The body not thickened anterior'lyj the head moderate, depressed, nearly squarej eyes small ; four extremely short antennae composed of but few joints, as in Phrosine, of various forms — the inferior being thin and styliform,. and the superior terminated by a small concave plate on the inner side — i-esemble a spoon or forceps(3). The others — Gammarin^, Latr. — always have four antennae j their body, invested with coriaceous and elastic tegments, is generally compressed and arcuated ; the posterior extremity of the tail is de- prived of fins J its appendages are styliform and cylindrical, or coni- (1) Cancer monoculoides, Montag'., Trans. Lin. Soc. XI, ii, .3; — Hyp^rie de Le- sueur, Lat, Encyclop. Mahod., Atl. d'Hist. Nat., CCCXXVIII, 17, 18; Desmar. Consid., p. 258. N.B. Near the Hyperix should be placed the genus Themisto, Lat., carefully figured and described in the Mem. de la Soc. d'Hist. Nat., tome IV. As in the Hyperiae, the eyes are very large and occupy the larger portion of the head; two of the antennae (the inferigr), all terminated by a multi-articulated stem tapering to a point, are evidently longer than the others. The part there called levre inferieure, is the ligula; those which appeared to form the third pair of jaws are the first of the foot-jaws, and, as in the Amphipoda and Isopoda, close the mouth inferiorly under the form of a lip. The four remaining foot-jaws ai-e very short, directed forwards and laid upon the mouth in such a way that they seem to constitute a part of it, so that if we do not count them, or if we merely consider the following locomotive and much more apparent organs as feet, this animal, like the Hyperia and Phrosine, appears at the first glance to have but ten feet instead of fourteen. The third pair of foot-jaws is terminated by a small didactyle forceps. The same pair of feet, properly so called, is much longer than the others; its penultimate joint is greatly elongated, and is armed with a range of small spines forming a sort of comb. But a single species is known. (2) Phros. macrophthalma, Risso, Journ. de Phys., Octob, 1822; Desmar., lb., p. 259; Cancer galba, Montag., Trans., Lin. Soc, XI, ii, 2. (3) Fhros. seminulata, Ilisso, lb.; Desmar., lb. The stem of the inferior antennae consists of two or thi-ee joints, while in Phrosine it is inarticulate. There also, the joints of the peduncles of the same antennae are shorter. Vol. Ill— M 90 CRUSTACEA. cal. At least two of their four anterior feet are usually terminated by a forceps. The vesicular bursse, in those where they have been observed — the Gammarin3e,Latr. — are situated at the exterior base of the feet, commencing with the second pair, and are accompanied by a small plate. The pectoral scales which enclose the ova are six in number. Sometimes the four antennae, although of different proportions in several, have a similar form and uses^ the inferior have no resem- blance to feet nor do they perform their functions. A subgenus which we have established under the denomination of loNE, Lat., Only, however, from a figure given by Montagu — Oniscus thora- ciciis, Trans. Lin. Soc. ,IX, III, 3, 4 — exhibits very peculiar charac- ters which separate it from all others of the same order. The body consists of about fifteen joints, but only distinguished by lateral tooth-like incisions. The four antennae are very short; those that are external, being longer than the others, are the only ones visible when the animal is seen on its back* Each of the two first segments of the body of the female is provided with two elongated, fleshy, flattened cirri resembling oars. The feet are very short, concealed under the body and hooked. The six last segments are furnished with lateral, fleshy, elongated, fasciculated appendages, which are simple in the male and like oars in the female. At the posterior extremity of the body we also observe six simple, recurved appen- dages, two of which are larger than the others. The abdominal valves are very large, cover the whole inferior surface of the body, and form a sort of receptacle for the ova. This animal remains concealed under the shell of the Calinassa subterranea, on the side of which it forms a tumour. Montagu, having v/ithdrawn one of these Crustacea from its domicil, kept it alive for several days. The female is always accompanied by the male, who fixes himself firmly to her abdominal appendages by means of his forceps. It is a rare animal which, in its habits, approaches the Bopyri(l). All the ensuing Amphipoda have the segments of the body per- fectly distinct, throughout their whole extent; in neither sex nor in any of the species do we find those long oar-like cirri observed in the first of the lones. (1) See Ann. des Sc. Nat., Decemb. 1826, XLIX, 10, the male— II, the fe- male. AMPHIPODA. 91 In the latter, when it exists, the movable toe of the foot, termi- nated by a forceps, is formed of a single joint. Of these last, there are some whose superior antennas are much shorter than the inferior, and even than their peduncle; the stem of the latter is composed of numerous joints. Orchestia, Leach. The second feet of the male terminated by a large forceps, the movable toe long and somewhat curvedj those of the female by two toes. The third joint of the inferior antennse is at most twice the length of that of the preceding ones(l). Taliprus, Lat. Neither of the feet forming a forceps. The third joint of the in- ferior antennse more than twice the length of that of the preceding onesj the antennae large and spinous(2). In the following, the superior antennae are never much shorter than the inferior. Some of them, furnished with elongated setaceous antennse ter- minated by a pluri-articulated stem, and without any remarkable forceps, approach the preceding in their superior antennae, which are somewhat shorter than the inferior, and are removed from those that follow by the form of their head which is narrowed before into a kind of snout. Such is Atylus, Leach(3). All those which succeed have the superior antennae as long as the inferior, or longerj their head is not elongated into a snout. Here, as in the five following genera of Leach, the peduncle of the antennae is formed of three joints(4). Some, in their superior antennae, present a character which is (1) Oniscus gammarellus, Pall., Spic. Zool., Fascic, IX, iv, 8; Cancer gamma- rus littoreus, Montag. ; Desmar., Consid., p. 261, XLV, 3. (2) Oniscus locusta, Pall., Spic. Zool., Fascic. IX, iv, 7; Cancer gammarus salta- tor, Montag.; Desmar., Consid., XLV, 11. (3) Mylus carinatus. Leach, Zool. Misc., LXIX; Desmar., Consid., p. 262, XLV, 4; Gammarus carinatus. Fab.; — G. nugax? ejusd. ; Phipps, Voy. to the North Pole, XII, 2? (4) The third joint of the peduncle may be very small and thus become assi- milateato the following, or those of the stem; this peduncle, as in the Dexamines, then appears to consist of but two joints. According to the system of Leach the stem is understood to form another but compound joint. 92 CRUSTACEA. unique in this order — the internal' extremity of the third joint of the peduncle is provided with a little articulated thread. It distin- guishes the Gammarus, Lat., Where the four anterior feet have the form of small forceps, the movable toe folding beneath. The species best known and the type of this subgenus is the Cancer pxilex, L.; Squillu pulex, De Geer, Insect., VII, xxxiii, 1,2. It inhabits brooks, etc. The other species are marine(l). The antennae of the following, as in all the other Amphipoda, are simple or without appendages. Melita, Leach. The second pair of feet, in the male, terminated by a large com- pressed forceps, the toe folding under its internal surface; the an- tennae nearly equal in length; a small foliaceous appendage on each side of the posterior extremity of the body(2). * M^RA, Leach. The second feet in the males terminated as in the Melitae, but the toe folds under the inferior edge of the forreps and is not concealed. The superior antennae are longer than the inferior, and the foliace- ous appendages of the posterior extremity of the body are want- ing(3). Amphithoe, Leach. The four anterior feet nearly similar in both sexes; the penultimate article or hand proper, ovoid(4). Pherusa, Leach. The Pherusae only differ from the preceding subgenus in the hand of the forceps, which is filiform(5). There, the peduncle of the antennae is only composed of two joints, (1) See Desmar., Consid., p. 265, 267. (2) Cancer palmatus, Montag., Trans., Lin. Soc, VII, p. 69; Encyclop. Method., Atl. d'Hist. Nat., CCCXXXVI, 31: Desmar., Consid., XLV, 7- (3) Cancer gammarus grosimanue, Montag., Trans. Lin. Soc, IX, iv, 5; Desmar. Consid. p. 264. (4) Cancer rubricatus, Montag., Trans. Lin. Soc, IX, p. 99; Encyclop. Method., Atl. d'Hist. Nat., CCCXXXVI, 33; Desmar., Consid., XLV, 9;— Om'sews cancellus. Pall., Spic. Zool. Fascic, IX, iii, 18; Gammarus cancellus. Fab. (5) Pherusa fusicola. Leach; Trans. Lin. Soc, XI, p. 360; Desmar., Consid., p. 268. AMPHIPODA. 93 the third being so small as to be confounded with those of the stem, or forming that of the base ; the superior are longer than the infe- rior. All the feet are simple, or without forceps. Such is Dexamine, Leach(l). In those, the movable toe of the two forceps is bi-articulated. The antennse are of equal length. Leucothoe, Leach. The antennse short, their peduncle formed of two joints; the four anterior feet terminated in a stout forceps; toes of the two first bi-ar- ticulated; those of the second pair consisting of a single and long joint(2). Cerapus, Say. Large antennae, the peduncle consisting of three — the superior — or four — the inferior — ^joints; the two anterior feet small, with a uni-articulated toe; the two following terminating in a large triangu- lar, smooth, dentated hand, with a bi-articulated finger. . Ceraphus tubularis, Say, Journ. Acad. Nat. Sc. of Philad., I, iv, 7 — 11; Desmar., Consid., XL VI, 2. It inhabits a little cy- lindrical tube, and in this respect approaches the subsequent subgenus. Very common at Egg Harbour, New Jersey, among, the Sertulariae on which it appears to feed. Finally, the inferior antennae, sometimes much larger than the superior, their stem consisting at most of four joints, have the form of feet, and appear to serve, at least occasionally, as organs of pre- hension. Rere the second feet are terminated by a large forceps. PoDocERus, Leach. Eyes very prominent(3). Jassa, Leach. Eyes not prominent(4). There, neither of the feet is terminated by a large forceps. (1) Cancer gammarvrs spmosua,MontSig., Trans. Lin. Soc, XI, p, 3; Desmar., Consid , XLV, 6. (2) Cancer articulosus, Montag., Trans. Lin. Soc. VII, 6; Desmar., Consid., p. 263, XLV, 5. (3) Podoeerus variegaius. Leach, Trans. Lin. Soc, XI, p. 361; Desmar., Consid. p. 269. (4) Joisa pulchella. Leach, lb., p. 361; Deimar., Consid., p. 269. 94 CRUSTACEA. CoROPHiuM, Lat. C. longicornis; Cancer grossipes^ L.; Gammarus longicorniSj Fab.; Oniscus volutator, Pall., Spic. Zool., Fascic. IX, iv, 9; Desmar., Consid., XL VI, 1, called Pernys, on the coast of Ro- chelle, lives in holes, which it forms in the mud, that is covered with hurdles, called boitchots, by the inhabitants- The animal does not make its appearance till the beginning of May. It wages everlasting war against the Nereides, Amphinomse, Arenicolae, and other marine Annelides, which inhabit the same locality. A curious spectacle is presented by these Crustacea, when the tide is coming in; myriads of them may then be seen moving in every direction, beating the mud with their great arms, and diluting it in order to discover their prey — is it one of the above men- tioned Annelides they have discovered, which is ten or twenty times larger than themselves.^ they unite to attack and devour it. The carnage never ceases until the mud has been thorough- ly turned up and its inequalities levelled. They do not even spare Molluscae, Fishes, or dead bodies on the shore. They mount upon the hurdles which contain Muscles, and fishermen assert that they will cut the threads that keep them there, in order to precipitate them into the mud, where they may devour them at their leisure. They appear to breed during the whole summer, as females carrying their ova are to be met with at various periods. Waders and different Fishes prey upon them. For these interesting observations we are indebted to M. D'Or- bigny, Senior, conservator of the Rochelle Museum and cor- responding member of that of Paris(l). The second section — Heteropa, Lat. — is composed of those with fourteen feet, the last four of which, at least, are unarmed and des- tined for natation only. It comprises two subgenera(2). Pterygocera, Latr. The thorax divided into several segments; four antennas furnished with setse or hairs in bunches; all the feet natatory and the last large (1) See Encyclop. Method., article Podocere. (2) This and the following section, in the first edition of the Regne Animal, form the second of the Isopoda, that of the Phytihranchiata. But independently of our having discovered mandibular palpi in some of these Crustacea, f he form of the subcaudal appendages appears to us to approximate them much nearer to the Amphipoda, than to the Isopoda. We may also obsei-ve that these animals, of which we have seen but very few, have not yet been well studied. AMPHIPODA. 95 and pinnated(l); cylindrical, articulated appendages to the posterior extremity of the body. Apseudes, Leach. — Eupheus, Risso. The thorax also divided into several segments, but the two ante- rior feet terminated by a didactyle forceps; the two following ones claviform, ending in a point and dentated on the edges; the next six slender and unguiculaled at the extremity; the last four natatory. The antennae are simple. The body is narrow, elongated, and has two long setaceous appendages at its posterior extremity(2). The third and last section — Decempedes, Lat. — is composed of Amphipoda, which present but six distinct feet. Typhis, Risso. But two very small antennae, the head large and eyes not promi- nent; each pair of feet annexed to its peculiar segment, and the four anterior terminated by a didactyle forceps. On each side of the thorax are two movable plates, forming a sort of lids or valves, which when joined, the animal folding up its feet and tail beneath, enclose the body inferiorly and give it a spheroidal appearance. The posterior extremity of the tail has no appendage(3). Anceus, Risso. — Gnathia, Leach. The thorax divided into as many segments as there are pairs of feet, but all the latter simple and monodactyle; four setaceous an- tennae; a stout square head with two large projections in the form of mandibles; extremity of the tail furnished with foliaceous fin-like appendages(4). (1) According- to the figure of Slabber — Oniscus arenarius, Encyclop. Method., Atl. d'Hist. Nat, CCCXXX, 3, 4, — the number of feet is but eight; reasoning from analogy, I presume it to be fourteen; besides, if the figure be exact, this genus would belong to the next section. (2) Eupheus ligioides, Risso, Crust., Ill, 37; Desmar., Consid., 285; — Apseudes talpa. Leach; — Cancer gammarus talpa, Montag., Trans. Lin. See, IX, iv, 6; Des- mar., Consid.: XLVI, 9. See the Gammarus heteroclitus, Viviani, Phosphor. Maris, II, ii, 12. N.B. The genus Rhcea, M. Edwards, Ann. des Sc. Nat. XIII, xiii. A, 292, dif- fers from the preceding in the superior antennae, which are stouter, longer, and bifid. (3) Typhis ovoides, Risso, Crust., If, 9; Desmar., Consid., p. 281, XLVI, 5. (4) Anceus forficularis, Risso, Crust., IT, 10; Desmar., Consid., XLVI, 6; — An- ceus maxillaris; Cancer maxillaris, Montag., Trans. Lin. See, VII, vi, 2; Desmar. lb., XLVI, 7. 96 CRUSTACEA. Praniza, Leach. Four setaceous antennae, as in the preceding; but the thorax viewed from above presents but three segments, the two first of 'which are very short and transverse, each supporting a pair of feet, while the third, much larger and longitudinal, supports the others. The feet are simple; the head is triangular, pointed before, and has prominent eyes. Each side of the posterior extremity of the body is also pro- vided with a fin(l). Various genera of Messrs Savigny, Rafinesque and Say(2), but the characters of which have not been described or sufficiently de- veloped, appear to belong to this order of the Amphipoda. Even some of the subgenera I have just quoted, require to be re-examined. M. Milne Edwards has made several valuable and detailed obser- vations on several of these Crustacea, which will most certainly tend to elucidate the subject. ORDER IV. LiEMODIPODA. The Laemodipoda are the only Malacostraca with sessile eyes, in which the posterior extremity of the body exhibits no distinct branchiae, and which are almost deprived of a tail, the two last feet being inserted in that extremity, or the seg- ment which connects them with it being merely followed by one or two very small joints. They are also the only ones in which the two anterior feet, that correspond to the second foot-jaws, form part of the head. They all have four setaceous antennse supported by a triar- (1) Oniscus ccerukatus, Montag., Trans. Lin. Soc, XI, iv, 2; Encyclop. Method., Atl. d'Hist. Nat., CCCXXIX, 28, and CCCXXIX, 24, 25; Desmar. Consid., XLVI, 8. (2) I can say nothing' of the G. ergine, l^isso: the number of its feet would seem to place it in the last section of the Amphipoda; while the manner in which they terminate, and the number of the segments of the body, appear to throw it among- the Isopoda. LiEMODlPODA. 97 ticulated peduncle, mandibles, without palpi, a vesicular body at the base of at least the four pairs of feet, beginning at the second or third pair, those of the head included. The body, usually filiform or linear, is composed of eight or nine seg- ments, including the head, and some small appendages in the form of tubercles at its posterior and inferior extremity. The feet are terminated by a stout hook. The four anterior, the second of which are the largest, are always terminated by a monodactyle forceps or a claw. In several, the four follow- ing ones are shortened, less articulated, without the terminal hook, or are rudimental, and nowise adapted for the ordinary uses of similar parts. The females carry their ova under the second and third segments of the body in a pouch formed of approximated scales. They are all marine Crustacea. M. Savigni considers them as allied to the Pycnogonides, and constituting with the latter the transition from the Crustacea to the Arachnides. In the first edition of this work they formed the first section of the Isopoda, that of the Cistibranchiata. We may unite them in a single genus which, by the law of priority, should be called the Cyamus, Lat. Some — the Filiforma, Lat. — have a long and very slendei* or linear body with longitudinal segments; feet equally slender and elongated, and the stem of the antennse composed of several small joints. They are found among marine plants, walk like the caterpillar termed the Geometra, sometimes rapidly revolving in a circle, or turning up their body, during which time the antennae are vibrating. While swimming, the extremities of their body are curved. Leptomera, Lat. — Proto, Leach. Fourteen feet, including the two annexed to the head, all complete and in a continuous series. Here, as in our Leptomera proper — Gammarus pedatus, Mull., Zool. Dan., CI, 1, 2 — all the feet, the two anterior excepted, have a vesicular body at their base. There, as in the Proto, Leach — Cancer pcdatus, Montag., Trans. Vol. IIL— N 98 CRUSTACEA. Lin. Soc, II, 6; Encyclop. Method., Atl.d'Hist. Nat. CCCXXXVI, 38 — those appendages are only proper to the second, and four fol- lowing feet(l). Naupredia, Lat. But ten feet, all in one continuous series; the base of the second and two following pairs provided with a vesicular body(2). Caprella, Lam. Ten feet also, but in an interrupted series, commencing with the second segment, exclusive of the head; both this segment and the following have two vesicular bodies, and are totally deprived of feet(3). The other — Ovalia, Lat. — Laemodipoda have an oval body with transversal segments. The stem of the antennae appears to be in- articulated, and the feet are short but slightly elongated; those of the second and third segments are imperfect and terminated by a long cylindrical joint without a hook; their base is provided with an elongated vesicular body. They form the subgenus Cyamus, Lat. — Laninda, Leach. I have seen three species, all of which live on the Cetacea; the most common, Onisciis ceti, L.; Pall., Spicil. Zool. Fascic. IX, iv, 14; Sqiiille de la Baleine, De Geer, Ins., VII, vi, 6; Pyc- nogonum ceti^ Fab.; Savig., M^m. sur les anim. sans verteb., Fascic, I, v, 1, is also found on the Mackerel: it is called by fishermen Pou de Baleine. A second very analogous species was brought to France by the late Delalande from the Cape of Good Hope. The third, which is much smaller, establishes itself on the Cetacea of the Indian Ocean. (1) We should also refer to the Leptomerse the Squilla ventricosa. Mull., Zool. Dan., LVI, 1 — 3; Herbst., XXXVl, ii: — the Cancer linearis, L., is perhaps a con- gener. He describes it as having six feet, but does not include the head. (2) A subgenus founded on a species from the coast of France, which appears to me undescribed. (3) The Squilla lohata. Mull., Zool. Dan., LVI, 4, 6; his Gammarus quadrilo- batus, lb., CXIV, 12; the Oniscus scolopendroides, Pall, Spic. Zool. Fascic, IX, iv, 15, are Caprellje, but their specific differences are not well characterized. We had referred the Cancer linearis, L., to the first, which, (see note one) now ap- pears doubtful. His Cancer Jiliformis is probably a Caprella; the Cancer phasma, Montag., Trans. Lin. Soc, VII, vi, 2, is a congener. His figure is copied Encyc. Method., All. d'Hist. Nat., CCCXXXVI, 37. For details concerning this order and genus, see the Nouv. Diet. d'Hist. Nat., Ed. H, and the work of Desmarest on the Crustacea. ISOPODA. 99 ORDER V. ISOPODA(l). T]ie Isopoda approach the Loemodipoda by the palpi of the mandibles being absent, but are removed from them in several other respects. The two anterior feet are not at- • tached to the head, and belong, as well as the following ones, to a particular segment. They are always fourteen in num- ber, unguiculated, and without any vesicular appendage at their base. The under part of the tail is furnished with very apparent appendages resembling leaflets or vesicular bursse, the two first or external of which, either partially or wholly, usually cover the others. The body is generally flattened, (1) The Polygonata, Fab., with the exception of the genus Monoculus. Messrs Audouin and Edwards — Ann. des Sc. Nat., Aout 1827, p. 379, 381 — have published some interesting obsei'vations on the circulation of the Isopoda, and on that of the Ligise in particular. The heart resembles a long vessel extended above the doi'sal surface of the intestine. From its anterior extremity arise three arteries, similar to those of the Decapoda. Lateral branches are also to be observed running from the heart towards the feet. On a level with the two first segments of the abdomen (the tail), that organ receives, from the right and left, small canals (branchio-cardiac vessels) which seem to proceed from the branchize. From their experiments on the Ligis, it would appear that the venous system is less complete than in the Decapoda macroura, and that the blood driven from the heart into va- rious parts of the body, passes into lacunae formed between the organs in the infe- rior part of the body which communicate freely with the afferent vessels of the branchiae. The blood having traversed the respiratory apparatus, returns to the heart through the branchio-cardiac vessels. This disposition would form the tran- sition from the circulating system of the Decapoda to that of certain Branchio- poda. According to Cuvier, the two anomalous cords which form the mediate portion of the nervous system of the Onisci — and, probably, of the other Isopoda and even of the Amphipoda — are not in complete juxtaposition, and may be dis- tinguished throughout their whole course. There are nine ganglions without counting the brain, but the two first and two last are so closely approximated that we may reduce the number to seven. The second and six subsequent ones fur- nish nerves to the seven pairs of feet; the four anterior, although, by the order of the parts, analogous to the four last foot-jaws of the Decapoda, are true feet. The segments which immediately follow, or those which form the tail, receive their nerves from the last ganglion; these segments may be considered as simple divi- sions of one segment represented by this ganglion; thus we find that the number of these posterior segments varies. 100 CRUSTACEA. or is wider than it is thick. The mouth consists of the same pieces as in the preceding Crustacea; but here, those which correspond to the two superior foot-jaws of the Decapoda, ex- hibit an appearance of a lower lip terminated by two palpi, still more than in the latter. The two mediate antennae are almost obliterated in the last Crustacea of this order, which are all terrestrial and also differ from the others in their re- spiratory apparatus. The male organs of generation are usually announced by linear or filiform appendages, and sometimes by hooks, situated at the internal origin of the first sub-caudal lamiucE. The females carry their ova under the thorax, either between scales, or in a pouch or membranous sac, which they open in order to allow a passage to their young, which are produced with the form of parts peculiar to their species, merely changing their skin as they increase in size. Most of them are aquatic. Those which are terrestrial, like all other Crustacea which live out of water, still require a certain degree of atmospheric humidity to enable them to breathe, and to preserve their branchiae in a proper state for the exercise of that function. This order according to the system of Linnaeus embraces the genus Oniscus, Lin., Which we will divide into six sections. The first — Epicarides, Latr. — is composed of parasitical Iso- poda, with neither eyes nor antennae, the body of which, in the male, is very flat, small and oblong; much larger in the female, and having an oval form narrowed and slightly curved posteriorly, hollow be- neath, with a thoracic border divided on each side into five mem- branous lobes. The feet are placed on this border and cannot be used either for locomotion or natation. The under surface of the tail is provided with five pairs of small, ciliated, imbricated leaflets, corresponding to as many segments and arranged in two longitudi- nal series; there is no appendage, however, to the posterior ex- tremity. The only parts distinctly visible in the mouth are two membranous leaflets laid upon another of the same nature, forming a large quadrilateral figure. The inferior concavity, forming a sort of shallow basket, is filled with the ova. Near their outlet is al- ways found the individual presumed to be the male. Its extreme ISOPODA. 101 smallness seems to forbid all possibility of copulation; according to Desmarest it is provided with two eyesj its body is straight and al- most linear. These Crustacea form but a single subgenus, that of BoPYRus, Lat., The most common species is the Bopynis crangorum, Lat., Gener. Crust, et Insect., I, 114; Monoculus crangorum^ Fab.; Fouger. de Bondar, Mem. de I'Acad. Roy. des Sc, 1772, pi, 1; Desman, Consid. XLIX, 8 — 13. It lives on the Palsemon ser- ratus, and the Pal. squilla, placed directly on the branchiae and under the shell; it occasions a tumour on one of its sides, re- sembling a wen. The fishermen of the British channel con- sider them as very young Soles or Plaice. A second species, the B. des palemons, has been described by Risso, under the female of which he observed eight or nine hundred living young ones(l). The second section — CYMOTHOADA,Lat. — comprises Isopodawith four very apparent setaceous antennae, almost universally terminated by a pluri-articulated stem; having eyes, a mouth composed as usual(2); vesicular branchiae arranged longitudinally and in pairs; the tail formed of from four to six segments, with a fin on each side near the end; and the anterior feet usually terminated by a small stout nail or claw. They are all parasitical. The eyes are sometimes placed on tubercles on the top of the head; the tail consists of but four segments. Serolis, Leach. But a single species is known, the Cymothoa paradoxa, Fab. The antennae are placed on two lines, and terminated by a pluri- articulated stem. Under the three first segments of the tail, between the usual appendages, there are three others, trans- versal and terminated posteriorly in a point(3). Sometimes the eyes are lateral and not placed on tubercles; the tail is composed of five or six segments. Here the organ of sight is not formed of smooth, granular, ap- proximated eyes; the antennas are placed on two lines, and consist of seven joints at least; the six anterior feet are usually terminated by a small, stout nail. (1) See the work of Desmarest, who has completely described this subgenus. (2) See our general observations on the Malacostraca with sessile eyes. (3) For other details consult Desmar., Consid., p. 2y2 — 294. 102 CRUSTACEA. In some, where the tail always consists of six segments, the length of the inferior antennae never surpassed the half of that of the body. We will begin with those whose mandibles, as usual, are but slightly, or in no degree salient. Cymothoa, Fab. The antennte nearly equal in length; eyes scarcely apparent; last segment of the tail forming a transverse square; the two pieces ter- minating the lateral fins, linear, equal and styliform(l). IcTHYopHiLus, Lat. — NerocUtt, Livoneca, Leach. The antennae, equal in length, and but slightly visible eyes; the last segment of the body almost triangular; the two pieces termi- nating the lateral fins in the form of leaflets or laminae, the exterior of which is largest in the Nerocilae, and of the size of the other in Livoneca(2). In the four following subgenera the superior antennae are mani- festly shorter than the inferior. In several, as in Cymothoa, all the feet are terminated by a small, stout, and strongly curved nail; the last eight are not spinous; the eyes are always separated and convex. They form three genera in the system of Leach, but may be united in a single subgenus, under the common denomination of one of them, or the Canolira, Leach. — ^nilocra, Olencira, Ejusd. The laminae of the fins in the 01encirae(3) are narrow and armed with spines. In the Anilocrae(4) the external leaflet of the same parts is longer than the internal; the reverse is the case with the Canolirae(5). The eyes, besides, are but slightly granulous while in the preceding that disposition is evident. In the three following subgenera, the second, third and fourth feet alone are terminated by a strongly curved nail, and the last eight are spinous. The eyes are usually but slightly convex; they are large and converge anteriorly. (1) Cymothoa asstrum. Fab.; Desmar., Consid., XLVI, 6, 7? — C. imbricata^ Fab. For the other species, see Desmar., Iog. cit. (2) See Desmar., op. cit., p. 307, genera Nerocila and Livoneca, and various spe- cies of Cymothoje of llisso, p. 310, 311. (3) Desmar., Consid., p. 306. (4) Desmar., Consid., Anilocre du Cap, XLVllI, 1. (5) Desmar, Consid., p. 305- ISOPODA. 103 ^GA, Leach. The two first joints of the superior antennse very broad and com- pressed, while in the two subsequent subgenera they are almost cy- iindrical(l). RociNELA, Leach. The Rocinelse differ from the -^gse, as just stated, in the form of the two first joints of their superior antennas, but otherwise approach them, as in their large eyes which approximate anteriorly(2). The CoNiLiRA, Leach, Resembles Rocinela in the antennae; but the eyes are smaller and distant, and the edges of the segments nearly straight and not falciform nor prominent(3). The last subgenus, among those of this section in which the an- tennse are placed on two lines, where the tail is composed of six segments, and the inferior antennae are always short, is distin- guished from all the preceding by strong and salient mandibles. It is the Synodus, Lat., A subgenus established on a single species(4). In those that follow, the tail is usually composed of but five seg- ments. The length of the inferior antennae is more than the half of that of the body. CiROLANA, Leach. The tail composed of six segments(5). In the Nelocira, Leach, It consists of but five. The cornea of the eyes is smooth(6). EuRYDicE, Leach. Similar to Nelocira in the number of caudal segments, but re- moved from it by the granulous eyes(7). (1) Desmar., Consid., p. 304, Mga entaillee, XLVII, 4, 5. (2) Desmar., Consid., p. 304. (3) Desmar., Consid., p. 304. (4) SeeEncyc. Method., article Synodus. (5) Desmar., Consid., p. 303. (6) Desmar., Consid., p. 302; N^locire de Swainsm, XLVIII, 2- (7) Desmar., Consid., p. 302. 104 CRUSTACEA. This subgenus leads us to those in which these organs are formed of granules or approximated simple eyes, and that also have the four antennae, composed of four joints at most, inserted on one hori- zontal line, and all the feet fitted for walking. The tail consists of six segments, the last of which is large and suborbicular. Such is the LiMxoRiA, Leach. The only living species known is the: Limnoria terebrans^ Leach, Edinb. Encyclop., VII, p. 433; Desmar. , Consid., p. 312. Although scarcely above two lines in length, its habits and fecundity render it highly noxious. It perforates the tim- bers of ships in various directions and with alarming rapidity. When taken in the hand it rolls itself into a ball. It is found in various parts of the British seas. The figure and description of a small fossil crustaceous ani- mal has been sent to Count Dejean by Professor Germar, which seems to us to belong to this subgenus(l). The third section — Sph^romides, Lat. — exhibits four very dis- tinct, short, setaceous or conical antennae, and a single genus — An- thura — excepted, always terminated by a stem divided into several small joints; the inferior, always the longest, are inserted beneath the under part of the first joint of ihe superior which is broad and thick. The arrangement of the mouth is as usual. The branchiae are vesicular or soft, exposed, and arranged longitudinally in pairs. But two complete and movable segments are observed in the tail, the first, however, frequently presents impressed and transverse lines indicating vestiges of others; on each side of its posterior ex- tremity is a fin terminated by two leaflets, of which the inferior alone is movable; the superior(2) is formed by an internal prolongation of the common stem. The branchial appendages are curved in- wards; the inner side of the first are accompanied, in the male, by a small linear and elongated projection. The anterior part of the head situated beneath the antennae is triangular, or has the figure of a heart reversed. Some have an oval or oblong body, usually assuming, when con- tracted, the form of a ball; the antennae terminated by a pluri-articu- lated stem, and the inferior, at least, visibly longer than the head. (1) The Oniscus praegustator, figured in Parkinson, is allied to this species, or at least appears to belong- to the same section. (2) It folds over the posterior edge of the last segment, and in several, such as the Zuzarx, and Nsesae, Leach, like an arch. TSOPODA. 105 The lateral and posterior fins are composed of a peduncle and two laminae, forming with the last segment a common fin shaped like a fan. In these, the impressed and transverse lines of the anterior seg- ment of the tail, which is always shorter than the next or last one, do not extend to the lateral margin. The first joint of the superior antennae has the form of a triangular palette. The head, viewed from above, forms a transverse square. The leaflets of the fins are much flattened, and the intermediate piece or the last segment is widened and rounded laterally. ZuzARA, Leach. Leaflets of the fins very large; the superior, Avhich is the shortest, separates from the other to form a border to the last segment(l). Sphjeroma, Lat. Leaflets of a moderate size, equal, and laid one over the other(2). In those, the impressed lines or transverse sutures of the anterior segment of the tail extend to its lateral edges and cut it. The first joint of the superior antennae forms an elongated square, or linear palette. The leaflets of the fins are usually narrower and thicker than in the preceding ; the external sometimes (Cymodocea) incloses the other, which is prismatic ; the point at which they unite resembles a knot or joint. Sometimes the sixth segment of the body is visibly longer through- out all its width than the preceding ones and that which follows. Only one of the two leaflets projects. Njesa, — Campecopea, Leach(3). Sometimes the sixth segment of the body is as long as the preced- ing ones and as that which follows. Cilic^a, Leach. Only one of the fin-leaflets salient, the other being placed against the posterior edge of the last segment(4). (1) Desman, Consid., p. 298. • • (2) Desmar., Consid., p. 299—302. Spherome denUe, XLVII, 3;—0niseuaser- ratus, Fab. (3) Desmar., Consid., Nes^e bidenti, XLVII, 2; — Campecop^e velue, Id., It., 1- (4) Desmar., Consid., Cilicee de Latreille, XLVIII, 3. Vol. III.— O 106 CRUSTACEA. Cymodocea, Leach. Both leaflets salient and directed backwards ; the sixth segment is not prolonged posteriorly, and the extremity of the last one pre- sents a small lamina in an emargination(l). Dynamene, Leach. Similar to the Cymodoceae in the projection and direction of the leaflets of the fins, but the sixth segment is prolonged posteriorly, and the last one exhibits a mere fissure without the lamina(2). The others, such as the Anthura, Leach, Have a vermiform body, and the antennae, composed of four joints, scarcely as long as the head. The leaflets of the posterior fins by their disposition and approximation form a sort of capsule. The anterior feet are terminated by a monodactyle forceps(3). In the fourth section — Idoteides, Leach — there are also four an- tennae, but they are placed on one horizontal and transverse line; the laterals terminate in a tapering, pointed, pluriarticulated stem ; the intermediaries are short, filiform or slightly inflated at the end, and consist of four joints, neither of which is divided. The compo- sition of the mouth is the same as in the preceding sections. The branchiae, white in most of them, are in the form of bladders, sus- ceptible of inflation, serving for natation and covered by two lami- nae or valvulae of the last segment that adhere laterally to its edges j they are longitudinal, biarticulated, and open in the middle on a straight line like folding doors. The tail consists of three seg- ments, the last of which is much the largest, and has neither termi- nal appendages nor lateral fins. They are all marine. Idotea, Fab. All the feet alike, and strongly unguiculated ; the body oval or simply oblong, and the lateral antennae shbrter than half the length of the body(4). (1) Desmar., Consid., XLVIIf, 4. (2) Desmar., Consid., p. 297. (3) Desmar., Consid., Anthftre grSle, XLVI, 13; Oniscus gracilis, Montag., Trans. Lin. Soc. IX, v, 6; — Gammarus heteroclitus, Vivian., Phosph. Mar., II, 11, 12. (4) Oniscus enfomon, L.; Squilla entomon, Deg-. , Insect., VII, xxxii, 1, 2; — Idotea triciispidata, Latr.; Desm., Consid., XLVI, ii. For the other species, see Idotea, Noviv. Diet. d'Hist. Nat., Ed. IT, and Desmar. op. cit. ISOPODA. 107 Stenosoma, Leach. The Stenosomae only differ from the Idotese in the linear form of their body, and the length of their antennae which is more than half that of the body(l). Arcturus, Lat. The Arcturi are very remarkable for the form of the second and third feet, which incline forwards and terminate by a long, bearded and unarmed or feebly unguiculated joint; the two anterior are laid on the mouth and are unguiculated; the last six are strong, ambu- latory, thrown behind, and bidentated at the extremity. In the length of the antennae and form of the body they approach the Ste- nosomae. I have never seen but a single species, the Arct. tuherculatus^ which was brought to Europe, from the Arctic seas, in one of the last expeditions to those regions. The fifth section — Asellota, Lat. — comprises Isopoda with four very apparent setaceous antennae, arranged on two lines, and termi- nated by a pluriarticulated stem; two mandibles; four jaws covered, as usual, by a kind of lip formed by the first foot-jaws; vesicular branchiae, in pairs, covered by two longitudinal and biarticulated, but free leaflets; a tail composed of a single segment, without late- ral fins, but with two bifid stylets, or two very short tubercular ap- pendages on the middle of its posterior edge. Other lamelliform appendages, situated at its inferior base, which are now numerous in the males, distinguish the sexes. AsELLus, Geoff. Two bifid stylets at the posterior extremity of the body ; eyes separated ; the superior antennae at least as long as the peduncle of the inferior ; the hooks at the end of the feet entire. The only species of this subgenus that is known — the Aselle d'eau douce, Geoff., Ins. II, xxii, 2; Squille aselle, Deg., Insect., VII, xxi, 1; Desmar., Consid., XLIX, 1,2; Idotea aquatica^ Fab., — is very abundant in fresh and stagnant waters as well as in the marshes, in the vicinity of Paris. Its gait, unless alarm- ed, is very slow. In the spring it issues from the mud in which (1) Stenosoma lineare, Leach; Desmar. op.cit. Ib.xlvi, 12; — Stenosoma hedicum, lb.; — Idotea viridissima, Risso, Crust., Ill, 8. For the other species, see Desmar. op. cit. 108 CRUSTACEA. it has passed the winter. The male, much larger than the fe- male, carries the latter for eight days, clasping her with the fourth pair of feet. When he abandons her she is loaded with a great number of ova inclosed in a membranous sac, situated under the thorax, which affords an issue to the young through a longitudinal fissure. Oniscoda, Lat. The Oniscodse or Janirae(l) of Leach differ from the Aselliin the approximation of their eyes, in the superior antennse which are shorter than the peduncle of the inferior, and in the hooks of the tarsi which are bifid. The only species known, the Janira maculosa^ Leach; Des- mar. , Consid. , p. 315, was found on the coast of England among the Fuci and Ulvae. J^RA, Leach, But two tubercles at the extremity of the tail in place of the stylets. But a single species has been described, the gsera albifrons^ Leach; Desm., Consid., p. 316, which is very common on the English coast among the Fuci and Ulvae. Finally, the Isopoda of the sixth and last section — Oniscides, Lat. — have four antennae also, but the two intermediate ones are very small, but slightly apparent, and are composed at most of but two joints; the lateral are setaceous. The tail consists of six segments, with two or four styliform appendages on the posterior margin of the last one, and. is without lateral fins. Some of them are aquatic and others terrestrial. In the latter, the first leaflets of the under part of the tail exhibit a series of small holes, through which air penetrates to the organs of respiration therein contained. In some, the sixth joint of their antennae, or the stem, is so com- posed, that by counting the little joints of this part the total num- ber amounts at least to nine. These Isopoda are marine and form two subgenera. The Tylos, Lat., Appears to possess the faculty of rolling itself into a ball. The (1) A name employed by Risso for a genus of the same class; I have conse- quently been obliged to replace it with another. ISOPODA. 109 last segment of the body is semicircular, and exactly fills up the emargination formed by the preceding onej the posterior appendages are very small and entirely inferior. The antennae consist of nine joints, the last four composing the stem. On each side is a de- pressed tubercle representing one of the intermediate antennae; the intervening space is raised. The branch'ias are vesicular, imbricated, and covered by laminae(l). LiGiA, Fab. The stem of the lateral antennae composed of a great number of small joints; two very salient stylets divided at the end into two branches, at the posterior extremity of the body. Ligia oceanica; Oniscus oceanicus, L., Desmar., Consid., XLIX, 3, 4, about an inch long, grey, with two large yellowish spots on the back. The lateral antennae are less than half the length of the body, and their stem consists of thirteen joints. The stylets are as long as the tail. This animal is very com- mon on the coast of France, where it is seen climbing up the rocks, &c. If an attempt be made to capture it, it quickly folds up its feet and lets itself fall. In the Ligia italica, Fab., the lateral antennae are nearly as long as the body; the sixth joint, or the stem, is divided into seventeen small ones. The stylets are much longer than the tail. Ligia muscorum; Oniscus hypnorum, Fab., Cuv., Journ. d'Hist. Nat. II, xxvi, 3, 4, 5; Oniscus agilis, Panz., Faun., Ins. Germ., Fascic. IX, xxiv. The lateral antennas shorter than the half of the body, and their stem composed of but ten small joints. The peduncle of the posterior stylets is furnished on the inner side with a tooth and seta. In others, all terrestrial, the lateral antennae consist at most of eight joints which gradually diminish in size towards the extremity, so that no one of them appears to be divided or compound. ^ Here, the posterior appendages, or stylets, project beyond the last segment. The body does not contract into a ball, or does it im- perfectly. Philoscia, Lat. The latenal antennae divided into eight parts and exposed at base; (1) Tylos armadillo, Lat., fig. in the pi. d'Hist. Nat. of the g^eat work on Egypt— from the Mediterranean. 110 CRUSTACEA. the four posterior appendages nearly equal. They are only found in wet places(l). Oniscus, Lin. The true Onisci have also eight joints in their lateral antennx, but their base is covered, and the two external appendages of the extremity of the tail are much larger than the others. These ani- mals, and those of the two following subgenera are vulgarly called Clous-a-porte, and by syncope Cloporte, Porcelets de Saint-Antoine{2). They inhabit retired and obscure places, cellars, fissures in walls, old buildings, under stones, &c., &c. They feed on decaying vege- table and animal matters, and seldom issue from their retreat, ex- cept in rainy weather. They move but slowly, unless they are alarmed. The ova are inclosed in a pectoral pouch. The young, at birth, have one thoracic segment less than the adult, and conse- quently have but twelve feet. They are no longer employed in medicine(3). PORCELLIO, Lat. The Porcelliones differ from the Onisci in the number of joints that compose the lateral antennae, which is only seven. In their other characters they are alike(4). There, as in Armadillo, Lat. The posterior appendages of the bodj< do not project j the last segment is triangular; a little lamina resembling a reversed trian- gle, or widest and truncated at the end, formed by the last part of the lateral appendages, fills, on each side, the space between that segment and the preceding one. The lateral antennae have but (1) Oniscus sylvestris. Fab.; Oniscus muscorum, Cuv., Journ. d'Hist. Nat. II, xxvi, 6, 8; Coqueb., 111. Icon. Insect, Dec. I, vi, 12. (2) These "Pigs of St Anthmy" are our FToorf-Zzce— BoUed in milk they still constitute a favourite remedy with numerous patients, and some few equally in- telligent practitioners, who attribute to them diuretic, absorbent, and aperient qualities. That they may act as an emetic, I can readily admit. Am. Ed. (3) Oniscus murarius. Fab.; Cuv., Journ. d'Hist Nat, II, xxvi, .11, 13; Le Clo- porte ordinaire, Geoff., Insect. II, xxii, 1; Cloporte aselle, Deg., Insect. VII, xxxv, 3; Desmar. Consid., XLIX, 5. (4) Oniscus asellus, Cuv., lb.; Panz., Faun. Ins. Germ., IX, xxi; Cloporte ordi- naire, var. C, Geoff.; — Forcellio Icevis, Latr.; Cloporte ordinaire, var. B, Geoff. ISOPODA. Ill seven joints. The superior subcaudal scales exhibit a range of small holes(l). (1) Oniscus armadillo, L.; Cuv., lb., 14, 15; Oniscuscinereus, Panz.,Ib., Fascic. LXII, xxii; — Oniscus variegatus, Vill., Entom., IV, xi, 16; Armadilk pustule, Des- mar., Consid., XLXIX, 6; — Armadilk des boutiques, Dnmer., Diet, des Sc. Nat., Ill, p. 117, a species from Italy formerly employed by the apothecaries. 112 CRUSTACEA. SECOND GENERAL DIVISION. ENTOMOSTRACA. Under this denomination, which is taken from the Greek and signifies Insects ivith shells, Othon Ei'ederick Muller comprises the genus Monoculus of Linnaeus, to which we must add some of his Lernaese. His investigation of these animals, the study of which is so much the more difficult as they are mostly microscopic, and the observations of Schseffer and of M. Jurine, Sen., have excited the admiration and secured the gratitude of every naturalist. Other but partial labours such as those of Randohr, Straus, Herman, Jun., Ju- rine, Jun., A. Brongniart, Victor Audouin, and Milne Ed- wards, have extended our knowledge of these animals and particularly of their anatomy ; but in this respect, Straus, as well as M. Jurine, Sen., although preceded by Randohr in the observation of several important details of organization, of whose memoir on the Monoculi, 1805, they seem to have been ignorant, has surpassed them all. Fabricius merely adopted the genus Limulus of Muller, which he placed in his class of the Kleistagnatha, or our family Brachyura of the order De- capoda. All the other Entoraostraca are united as by Lin- naeus in one single genus, Monoculus, which he places in his class of the Polygonata or our Isopoda. These animals are all aquatic and mostly inhabit fresh wa- ter. Their feet, the number of which varies, and that some- times extends to beyond a hundred, are usually fitted for natation only, being sometimes ramified or divided, and some- times furnished with pinnulai or formed of lamellae. Their brain is formed of one or two globules. The heart has always the figure of a long vessel. The branchiae, composed of hairs or seta?, singly or united, in the form of barbs^ combs or tufts, ENTOMOSTKACA. 113 constitute a part of those feet or of a certain number of them, and sometimes of the upper mandibles(l). Hence the origin of our term Branchiopoda, affixed to these animals, of which at first we formed but a single order. Nearly all of them are provided with a shell composed of one or two pieces, very thin, and most generally almost membranous and nearly diaphanous, or at least with a large anterior thoracic segment, frequently confounded with the head, which appears to re- place the shell. The teguments are usually rather horny than calcareous, thereby approximating these animals to the Insecta and Arachnides. In those which are provided with ordinary jaws, the inferior or exterior are always exposed, all the foot-jaws performing the office of feet properly so called, and none of them being laid upon the mouth. The second jaws, those of the Pliyllopa at most excepted, resemble these latter organs ; Jurine sometimes distinguishes them by the name of hands. ^ These characters distinguish the gnawing Entomostraca from the Malacostraca ; the others, those which constitute our order of the Poecilopoda, cannot be confounded with the Malacostraca, inasmuch as they are deprived of organs of mas- tication, or because the parts which ,sfeem to act as jaws are not united anteriorly nor preceded by a labrum as in the an- tecedent Crustacea and the gnawing Insecta, but are simply formed by the branches of the locomotive organs, which, for that purpose, are furnished with small spines. The Poecilo- poda in this class of animals represent those which in that of Insects are knoAii^by the name of Suctoria or the Suckers. Nearly all of them are parasitical, and they seem to lead to the Lernsese by insensible gradations ; but the presence of eyes, the faculty of changing their skin, or even of undergo- ing a sort of metamorphosis(2), and that of locomotion by (1) See Cypris. ■ (2) The young of Daphnia, and of some neighbouring- subgenera, and probably also those of Cypris and Cytherea, with the exception of size, scarcely differ, if at all, from their parents on quitting the eg^\ bitt those of Cyclops, the P%llopa, and the Arguli, experience considei'able changes while young, either as respects Vol. III.— P 114 CRUSTACEA. means of their feet, appear to us to establish a positive line of demarcation between the former and the latter. We have consulted several erudite naturalists with respect to these transformations, but none of them have observed a change of skin to occur. The antennse of the Entomostraca, whose form and number greatly vary, serve for natation in several. The eves are rarely placed on a pedicle, and when this is the case, that pedicle is a mere lateral prolongation of the head, and is never articulated at base ; they are frequently closely ap- proximated and even form but one. The organs of genera- tion are situated at the origin of the tail ; it hcjs been thought, but erroneously, that their seat was in the antennse of the male. This tail(l) is never terminated by a fan-like fin, nor does it present those false feet observed in the Malacostraca. The ova are collected under the back, or are external, and covered by a common envelope, and resemble one or two small clusters at the bast of the tail ; it appears that they can be kept in a desiccated state for a long period without losing their properties. It is only after a third change of skin that these animals become adult and capable of continuing their species. It has been proved, with resplct to some of them, that a single copu- lation fecundifies several successive generations. ORDER I. • BRANCHIOPODA. A mouth composed of a labrum, two mandibles, a ligula, and one or two pairs of jaws, and branchiae, the first of the form of the body or the number of feet. Tfeese organs in some, the Arguli for instance, experience changes which modify their uses. (1) If we except the Phyllopa, the last feet are thoracic, or foot-jaws (Cypns). BRANCHIOPODA. 115 wliich^ when there are several, are always anterior, charac- terize this order or the sixth of the class. These Crustacea are always wandering and are generally protected by a shell resembling that of a bivalve, and fur- nished with four or two antennae. Their feet, with a few exceptions, are wholly natatory. Their number varies, be- ing but six in some, while in others it amounts to twenty, for- ty-two, or more than a hundred. Many of them have but one eye. Most of these animals, as we have already stated, being nearly microscopical, it is evident that the application of one of the characters we have employed — that of the presence or absence of the palpi of the mandibles — with respect to them, presents almost insuperable difficulties(l). The form and number of the feet, that of the eyes, the shell, the antenna, furnish us with more visible marks, and such as are within the observation of every one. This order in the systems of De Geer, Fabricius and Lin- naeus, a single species excepted — M. polyphemus^ contained but the single genus MoNOCULUs, Lin. (2) Which we will divide into two principal sections. The first, — that of the Lophyropa — is distinguished by the number of feet, which never extends beyond ten; their joints are also more or less cylindrical or conical, and never entirely lamelliform or foli- aceous? the branchise are but few in number, and most of them have but one eye. Several, besides, have mandibles provided with a palpus(3); there are, almost always, four antennse which serve for locomotion. In the second section — that of the Phyllopa — the number of feet is increased to at least twenty, and in some amounts to many more; their joints, or at least the last ones,^are flattened and resemble cili- (1) We will beg-in, however, with those Branchiopoda whose mandibles are furnished with palpi; they constitute the two first divisions of the Lophyropa. (2) And that of Binode in the system of Geoffroi. (3) M. Straus appears to attribute this charactei' exclusively to Cypris and Cy- therea, which compose his order of the Ostrapoda; but from the observations of Jurine, Sen., and Handohr, it seems that it also belong's to CJyclops. 116 CRUSTACEA. ated leaflets. The palpi of the mandibles are always wanting. They all have two eyes, situated in some at the extremity of two movable pediclesj their antennse, but two in number in several, are generally small and not fitted for natation. We will divide the Lophyropa into three principal and very natu- ral groups, the two first of which approach the Crustacea of our three first orders in their mandibles, each of which is furnished with a palpus, and in some other characters. 1. Those — Carcinoida, Lat. — whose more or less ovoid shell is not doubled like that of a bivalve, and leaves the inferior portion of the body exposed. They never have antennae resembling ramified arms. They have ten feet, more or less cylindrical or setaceous. The ova, in those females whose gestation has been observed, are contained in two external sacs situated at the base of their tail. Some of them have eyes. 2. Those — OsTRAcoDA, Lat. 5 Ostrapoda, Straus — whose shell is formed of two pieces or valves resembling those of a muscle, united by a hinge, and closing while the body is quiescent. They have but six feet(l}, neither of which terminates in a digitated fin, nor is ac- companied by a branchial lamina. Their antennae are simple, fili- form or setaceous. They never have more than one eye. Their mandibles and superior jaws are furnished with a branchial leaf. The ova are placed under the back. 3. The last — Cladocera, Lat.; Daphnides, Straus — have but one eye, and the shell doubled but without a hinge (Jurine), termi- nating posteriorly in a point, und leaving the head, which is cover- ed by a kind of shield like a rostrum, exposed. They have two, usually very large, antennae, resembling arms, divided into two or three branches directly above the peduncle, which are furnished with threads, always projecting and serving as oars. Their ten feet(2) are terminated by a digitated or pectinated fin accompanied, the two first excepted, by a branchial lamina(3). Their ova are also placed under the back; their body always ter- minates posteriorly in the manner of a tail, with two or three threads at the end. The anterior extremity of the body is sometimes pro- _ _ . (i; According to Straus, the first pair of feet; but although these parts by serv- ing- as oars perform their functions, I nevertheless consider them as analogous to the lateral antennae of the superior Crustacea and to the two superior ones of a Cyclops, which here also concur with the feet in producing locomotion. (2) MuUer gives eight to the Cytherese; reasoning from analogy, we may pre- sume that he was mistaken. (3) This character applies especially to Daphnia, the most numerous subgenus of this division, and by analogy, to Polyphemus and Lynceus. BRANCHIOPODA. 117 longed into a kind of rostrum, and at others forms a kind of head, almost entirely occupied by a large eye. The first division of the Lophyropa Branchiopoda— that of the Carcinoida — may be divided into two according to the number of the eyes. Some of them have two. Here the shell completely invests the thorax; the eyes are large and very distinct, and the intermediate antenna are terminated by two threads. ZoEA, Bosc. Very large globular eyes completely exposed, and horn-like pro- jections on the thorax. Zoea j)elagica, Bosc, Hist. Nat. Crust. II, xv, 3, 4. The body semi-diaphanous; four antennae inserted under the eyes, the exiternal ones bent into an elbow and bifid; a kind of long rostrum on the forepart of the thorax and between the eyes, and a long pointed prominence on the posterior part of the back. The feet are very short and hardly visible, the two last excepted, which are elongated or terminate in a fin. The tail is as long as the thorax, curved, and formed of five joints, the last being large, crescent-shaped and spinous. It was discovered by Bosc in the Atlantic Ocean. The Monoculus taurus, Slabber, Microsc. V, and the Cancer germanus, L., appear to be allied to it(l). Nebalia, Leach. Triangular, flattened eyes, partly covered by a triangular and arched scale. The feet are forked, and the terminal appendages of the tail seta- ceous(2). (1) See the Hist. Nat. des Crust, et des Insect., of Latreille, and the work of Desmarest on the Crustacea. This g'eniis has not yet been completely described, and we have not been able to procure a sing-le specimen of it. (2) Nebalia Herbstii, Leach, Zool. Miscell., XLY; Desmar. , Consid., XL, 5; Rand., Monoc. I, 8? The Nebalie ventrue, Risso, Journ. de Phys., Octob. 1822, probably forms a pe- culiar subgenus in the section of the Schizopoda. In the Cyclops exiliens, Viviani, the thorax is divided into several segments, a circumstance which excludes it from the Nebalix. It also forms a new subgenus intermediate between the preceding and fbllowing one. N.B. A new species of thi* genus, the N. Geoff. Saint-Hil., lb., XV, 1, has been very minutely described by Milne Edwards. The head is terminated anteriorly by 118 CRUSTACEA. There, the thorax or the shell, viewed from above, is divided into five segments, of which the first is much the largest and has the an- tennae, eyes, and foot-jaws attached to it; the second and the third have each one pair of feet, the fourth has the two following pairs, and the fifth, the last. The eyes are small and not prominent; all the antennae are terminated by a single thread. CoNDVLURA, Lat. The inferior antenns longest; the anterior sides of the first seg- ment prolonged into a point forming two scales approximated into a kind of rostrum; feet terminating in a silky point; some of the intermediaries, as in the Schizopoda, with an external appendage near their base; the tail narrow and formed of seven annuli, the last of which, conical and elongated, projects between the two lateral appendages that are slender, styliform, and composed of two joints, the last silky (1). We should remark, that the genus Nicothoe of MM. Audouin and Milne Edwards, by admitting it to have mandibles and jaws, would belong to this section; but as the animal on which it is founded is parasitical, and, as I think I perceived in it a vestige of a sucker, I have placed it among the Poecilopoda. I would observe, however, that the feet, the anterior excepted, closely resemble those of Cyclops, and that the females also carry their ova in two sacs situated at the base of the tail as in the latter genus(2). a rostrum articulated at base, or movable and pointed; the eyes are pedunculated; the superior antennae are inserted under them, and the second joint of their pe- duncle is furnished with a lamina; the mouth is surrounded witii three pairs of ap- pendages whicli appear to us to correspond in their progressive order to the pal- pigerous mandibles and four jaws of the Crustacea Decapoda; beneath are placed five pairs of foliaceous and ciliated lamins which appear to be brancliial, and fur- ther down are four pairs of bifid and natatory feet; the abdomen is composed of seven annuli, the first of which support two small rudimental filaments; the last is terminated by two elongated stylets furnished with long hairs. As it is extremely probable that there is, as usual, another pair of feet, the two inferior and branchial appendages above mentioned, may very well represent that pair. In the other appendages we should find foot-jaws and the parts of the ligula; in that case the Nebalis must be referred to the last section of the Decapoda Macroura. (1) Condylura DorbigJii, Lat. From the sea coast of Uochelle. (2) Near the Condylurs should be placed the genus Cuma, M. Edwards, Ann. ECILOPODA. 145 In some, the four anterior feet, at least in one of the sexes, are terminated by a single toe. But a single species of this division is known; it is the Limu- lus heterodactyhis, and is the type of the genus Tachypleus, Leach(l). I have seen it figured on Chinese vellums. In the others, the two anterior claws at most, are alone monodac- tyle. All the ambulatory feet are didactyle, at least in the females. This division is composed of several species, which, owing to the little attention that has been paid to the detailed form of their parts, to the differences resulting from sex and age, and from their pecu- liar localities, have not yet been characterized in a rigorous and comparative manner. The common American Limulus for instance, when young, is whitish or of a light colour, and has six stout teeth along the whole ridge of the middle of the upper shell, and two others equally strong and pointed on each lateral ridge of the shield or of the first piece of that shelly while older specimens, sometimes more than a foot and a half in length, are of a deep brown colour or almost blackish, their teeth, the middle ones especially, being al- most obliterated. Here also the lateral margins of the second piece of the shell are marked with fine dentations which are scarcely ap- parent or wanting in the former. We should consider as young individuals the Lini. cyclops^ Fab., and the Z. Sowerhii, Leach, Zool. Miscell., LXXIV; his L. tridentatus, and the L. albus, Bosc: and as older ones, my Limule des Moluques; Monoculus polyphemus, L.; Clus., Exot., lib. VI, cap. xiv, p. 128j Rumph., Mus., XII, a, b, which I at first considered a distinct species, under the belief that these large individuals inhabited those islands exclusively. In all of them, or at all ages, the tail is somewhat shorter than the body, and triangular, the upper ridge finely denticulated and without any decided sulcus beneath. We will designate this species by the name of Limulus polyphemus. These latter characters will distinguish it from some others described by Dr Leach(2). shell, in lieu of spines, merely form smaller teeth articulated at base; but these ar- ticulations have perhaps disappeared. (1) This Limulus is perhaps the Kabutogani or Unkia of the Japanese, and re- presents the constellation of Cancer on their primitive Zodiac. (2) See Nouv. Diet. d'Hist. Nat. Ed. II; Desmar., Consid., p. 344 358. Vol. III.— T 146 CRUSTACEA. FAMILY II. SIPHONOSTOMA. The Siphonostomfc have no kind of jaws whatever. A sucker or siphon, sometimes external and in tlie form of an acute inarticulated rostrum(l), and at others concealed or but slightly visible, fulfils the functions of a mouth. There are never more than fourteen feet. The shell is very thin and composed of a single piece. They are all parasitical. We will divide this family into two tribes. The first — Caligides, Lat. — is characterized by the pre- sence of a shell resembling an oval or semi-lunar shield ; by the number of visible feet, which is always twelve, — or four- teen, if we include those which Leach considers as such, and which I call inferior antennae; by the form and size of the tenth pairs which are sometimes multifid, pinnate or ter- minated in a fin, and well adapted at all times and in the adult, for the purposes of natation, and sometimes foliaceous, or broad and membranous. The sides of the thorax are never furnished with wing-like expansions directed backwards and enclosing the body posteriorly. Here, the body, exhibiting several segments above, is elongated and narrowed posteriorly, terminating in a kind of tail with two threads or as many other salient appendages at the end; this extremity is not covered by a segment of the superior teguments in the form of a large rounded scale, deeply notched in the posterior margin. The shell is at (1) The composition of this rostrum or beak is not well known. It is evident, from tlie figure of the Argulus foliaceus, given by Jurine, Jun., that it contains a sucker; but is this the case with the others, and of how many pieces is it com- posed? I cannot answer the question. I presume, however, that this siphon con- sists of the labrum, mandibles and the ligula which forms the sheath of the sucker. In the preceding Entomostraca, the four anterior feet, whose form is very differ- ent from that of the following ones, would correspond to the four jaws of the De- capoda. P^CILOPODA. 147 least half the length of the body. This subdivision will com- prise two genera of MuUer. Argulus, Mull. This genus was at first designated under the name of Ozolus, and but very imperfectly described. Jurine, Jun. has since studied its type with the most scrupulous attention, followed it throughout all its changes of age, and produced a perfect and complete monograph of it. He has restored to the genus the original name given by Miiller. The Arguli are furnished with an oval shield, posteriorly emargi- nated, covering the body, the posterior extremity of the abdomen excepted, and bearing on a mediate, triangular space distinguished by the name of clypeus, two eyes, four very small, almost cylindri- cal antennae placed in front, the superior of which, shorter and tri- articulated, have a stout, edentated and recurved hook at their basej and the inferior quadriarticulated, with a small tooth on the first joint. The siphon is directed forwards. There are twelve feet. The two first terminate in a transversely annulated disk, striated and edentated along the margin, and presenting internally a sort of rosette formed by the muscles, and apparently acting in the manner of a cup or sucker. Those of the second pair are prehensile, the thighs large and spinous, and the tarsi composed of three joints, the last of which is provided with two hooks. The remaining feet are terminated by a fin formed of two elongated pinnulae, whose edges are fringed with bearded threads: the two first of the latter, or those of the third pair, including the four that precede them, have an ad- ditional but recurved toe. The two last are annexed to that portion of the body which projects posteriorly from the shell, or the tail. The female has but a single oviduct covered by two small feet situ- ated behind the two palettes. The organ which is considered as the penis of the male, is placed at the internal extremity of the preceding joint of the same feet near the origin of the two toes. On the same joint of the two preceding feet, and facing these organs of copula- tion, is a vesicle presumed to be seminal. The abdomen, by which we mean that part of the body which extends posteriorly from the ambulatory feet, the rostrum, and a tubercle containing the heart, is entirely free, without distinct articulations, and terminates directly after the last feet behind, by a sort of tail, in the form of a rounded lamina, deeply emarginated or bilobate, and without terminal hairs: it is a species of fin. The body is so transparent that the heart may be distinguished through its parietes. It is situated behind the base of the siphon, lodged in a solid tubercle, semi-diaphanous and 148 CRUSTACEA. composed of a single ventricle. The blood, formed of little diapha- nous globules, is impelled forwards in a column which soon divides into four branches, two of which proceed directly towards the eyes, and two towards the antennas; the latter are then reflected back- wards and united to the former, constituting a single column on each side, which descends towards the cup, turns round its base, and disappears. A little beneath the two following feet, we may distinguish on each side, another sanguineous column which curves outwards, extends along the borders of the shell, and having reached the two penultimate feet, is flexed forwards and ceases to be visible. Another, where, as in the preceding, the blood flows from the ante- rior part of the body to the posterior, traverses longitudinally the middle of the tail; it unites behind with two other currents that may be seen on the edges of the tail, but which flow in a contrary direc- tion, or appear to return the blood to the heart. Jurine avoids using the term vessel, because the blood which is driven into the anterior part of the body, appears to be diff"used there in such a manner, as to induce us to believe that its globules, instead of being contained in particular vessels, are dispersed in the parenchyma of those parts. From what we have stated, however, with respect to the circulation in the Decapoda, it is evident, that the blood, in the first instance, is distributed in the Arguli in the same way, and that the currents or columns of which we have just spoken, seem to indicate the exis- tence of peculiar vessels. This able observer, in fact, subsequently acknowledges that the circulation is not every where carried on in so diff"used a manner as in the anterior part of the shell, where, how- ever, in our opinion, it is effectuated as in the Decapoda. The brain, which is situated behind the eyes, appeared to him to be divided into three equal lobes, one anterior and two lateral. The anterior part of the stomach gives origin to two large appendages, each divided into two branches, which ramify in the wings of the shell. The brownish coloured aliment they contain renders these ramifications visible. The caecum is provided near its origin with two vermiform appendages. The excessive ardour of the males frequently induces them to mistake one sex for the other, or to make their advances to preg- nant or dead females. They are placed in coition on their back, to which they cling by means of their feet with cups, for several hours. The period of gestation is from thirteen to nineteen days. The ova are smooth, oval and milk-white. They are fixed with gluten on stones or other indurated bodies, either in a straight line or in two ranges, and from one to four hundred in number; being pressed against each other, their form becomes almost hexagonal. Twenty-five days after the extrusion of the ova, and after they P^CILOPODA. 149 have assumed a yellowish and opaque tinge, the eye and parts of the embryo are perceptible. In about ten days more, the shell opens longitudinally, and the tadpole issues from it, being at this period about three-eighths of a line in length. Its general form is similar to that of the adult, but the organs of locomotion present a very essential difference. Muller has described it in this state by the name oi Argulus charon. Four oars or long arms, two situated before the eyes and two behind, each terminated by a pennate and flexible pencil of hairs that have a simultaneous motion, by which the animal is impelled by jerks, project from the anterior extremity of the shell: they do not represent the antennae, for they also are visible. The feet with cups are replaced by two stout feet, flexed into an elbow near the extremity, and terminated by a stong hook, with which it clings to Fishes. The only feet proper to the adult, that are developed and free, are those of the second and third pairs, or the two ambu- latory and the two first natatory feet; the following ones are as yet fixed to the abdomen. The heart, proboscis, and ramifications of the appendages of the stomach are distinct. After the first change of tegument, which is effected by a laceration of its inferior surface, the oars disappear, and all the natatory feet are visible. In three days more the second change ensues, but without producing any important alteration. But after the third, which occurs forty-eight hours subsequently to the second, these same feet are converted into those with cups, still, however, preserving the terminal hook. At the expiration of nine days, there is a new change of skin, and the organs of generation, male and female, are apparent; another change of tegument however is required ere the sexes are fitted for copula- tion, so that the period of their metamorphosis extends to twenty-five days. Still, however, they have attained but the half of their proper size. For that purpose fresh changes of the tegument, which occur every six or seven days, are requisite. Jurine satisfied himself of the fact, that propagation never ensues without the intervention of the male. The females, which he kept separate, perished from a disease which was announced by the appearance of several brown globules, arranged in a semicircle on the posterior portion of the clypeus, and apparently formed in the parenchyma, for they were not dispersed by the change of tegument. Jirgulus foUaceus, Jurine, Jun., Ann. Mus. d'Hist. Nat. VII, xxvi; Monoculus foUaceus, L.; Argulus delphinus, Herm. Jun., Mem. Apter., V, 3, VI, ii; Monoculus gyrini, Cuv., Tabl., Elem. de I'Hist. Nat. des Anim., p. 454; Ozolus gasterosteU Lat., Hist. Nat. des Crust, et des Insect., IV, xxix, 1 — 7; Des- mar., Consid., L. ; Louse of the Stickleback, Baker, Micros., II, xxiv. This species, the only one of the genus that is known, 150 CRUSTACEA. attaches itself to the under part of the body of the tadpoles of Frogs, of that of the Stickleback or Gasterosteus, and sucks its blood. The body is flattened, of a light yellowish green colour, and about two lines and a half in length. Hermann, Jun., who has well described this Argulus in its perfect state, and who quotes a manuscript of Leonard Baldaneur a fisherman of Stras- bourg, dated 1666, in which the same animal is figured, says, that in the environs of that city it is seldom found, except on the Trouts, and that it frequently kills them, those especially which are kept in ponds; it is also found on the Perch, Pike, and Carp. He has never found it on the gills. It has a habit of whirling round like the Gyrini. He says that the body is di- vided into five rings, but slightly distinct on the back. Caligus, Mull. Neither of the feet with cups; those of the anterior pair unguicu- lated; the others divided into a greater or less number of pinnulae or membranous leaflets. A considerable portion of the body is not co- vered by the shell, and is usually terminated posteriorly by two long threads, and sometimes by fin-like or styliform appendages(l). The vulgar name o( Jish-loiise, by which they are collectively de- signated, announces their habits to be similar to those of the Arguli and other Siphonostomse. Several naturalists have considered the tubular threads at the posterior extremity of their body as ovaries; I have sometimes found ova under the posterior and branchial feet, but never in these tubes. Besides, external oviducts thus prolonged are never met with except in females whose eggs are to be deposited in deep holes and cavities — now this is not the case with the Caligi. Miiller and other zoologists have remarked that these Crustacea erect and agitate the appendages in question. We believe with Ju- rine, Jun., and such also is the opinion of his father, that they serve for respiration, like the terminal filaments of the abdomen of an Apus(2). (1) The interval also frequently exhibits other, but smaller or much less salient appendages. (2) In the Ann. Gener. des Sc. Phys., vol. Ill, p. 343, Brussels, is an extract from the observations of Dr Surriray on the foetus of a species of Caligus which he believes to be the elongatus, and which is very common on the operculum of the Esox belone. That gentleman informs us that by pressing the two caudal threads of the animal in question, a number of transparent and membranous ova were ex- truded, each of which contained a living foetus, very different from the mother, and of which he gives a description. From these observations we might be in- duced to conclude that these threads are a kind of external oviducts: but is thera P^CILOPODA. 151 Some of them whose feet are free, and (the two last excepted) annexed to the anterior part of the body — Cephalothorax, Lat. — covered by the shield, in which some of the posterior feet are fur- nished with numerous and pennated threads, and in which the si- phon is not apparent, have the abdomen naked above and termi- nated by tv/o long; threads, or as many stylets; they compose the subgenus Caligus, properly so called. — Caligus risculus, Leach(l). In all others, the superior surface of the body is imbricated, or that portion of the body is enclosed in a kind of case formed by the last feet which resemble membranes and fold over it. Of these latter, there are some whose antennae never project like little claws, whose feet are free, and whose last ones do not envelope the body like a membranous case. They form the following sub- genera. Pterygopoda, Lat. — Nogaus? Leach. Where the posterior extremity of the body is terminated by two kinds of finsj where the under part of the post-abdomen or of the second division of the body, not covered by the shield, is furnished with pinnated or digitated feetj and where there is a distinct pro- boscis or rostrum(2). Pandarus, Leach. Two threads at the posterior extremity of the body; the first and fifth pairs of feet unguiculated, and the remainder digitated; no ap- parent siphon(3). DiNEMOURA, Lat. Two long anal filaments and an apparent siphon; the two anterior feet unguiculated; the two following ones terminated by two long toes, and the remainder membranous leaflets(l). no mistake in this ? I have studied these same organs in various specimens — pre- served in spirits, it is true — but could never discover any body whatever. (1) Caligus piscinus, Lat.; Cal. curtus, Miill. Entom., XXI, 1, 2; Monoculus pis- cinus, L.; Cal. Mullen, Leach; Desmar., Consid., L, 4; found on the Cod. The Oniscus lutosus, Slabber, Encyclop. Method., Atl. d'Hist. Nat. CCCXXX, 7, 8, from the fin-like appendages of its tail, seems to indicate a separate subgenus. The Binocle ^ queue en plumet, Geoff., might be placed in it. (2) A single living species found on the Shark. See the genus Nogaus, Des- mar., Consid., p. 340. (3) Pandarus bicolor, L«ach; Desmar., L., 5; Pandarus Boscii, Leach, Encyc. Brit. Suppl. I, XX. For the otlier species, see Desmar., lb., p. 339. (1) Caligus produdus, Miill., Entom. XXXI, 3, 4; Monoculus sahnoiieun. Fab. 153 CRUSTACEA. The last subgenus of this subdivision, that of Anthosoma, Leach, Approximates to Dinemoura in the presence of a siphon, and in the two caudal threads; but it is removed from it, as well as the preceding- ones by its projecting antennae which resemble little mo- nodactyle claws, and by its six last feet which are membranous, united inferiorly, and folded laterally over the post-abdomen, en- veloping it like a case; those of the first and third pairs are ungui- culated; the second feet are terminated by two short and obtuse toes(2). There, the body is oval, without salient caudiform appendages, composed of threads or fin-like productions at its posterior extre- mity. A portion of the superior teguments forms a shield, which does not cover its anterior half, is rounded and emarginated before, widened and as if bilobate behind; then follow three pieces or scales, posteriorly rounded and emarginated, the second of which, and the smallest of the three, is almost in the form of a reversed heart; the last, and the largest, is arched. The four posterior feet are in the form of laminae, and are united by pairs; those of the first and the third are unguiculated; the extremity of the second is bifid. The siphon is apparent. The ova are covered by two large, oval, conti- guous, coriaceous pieces, placed under the abdomen, and surpassing it in length. Such are the characters of the genus Cecrops, Leach, Of which a single species only is known. Cecrops Latreillii, Leach, Encyc. Brit.,Supp. I, xx; 1, 3, the male; 2, 4, the female; 5, the antennae magnified; Desmar., Con- sid. L, 2. Found on the branchiae of the Tunny and Turbot. The second tribe, that of the Lerneiformes, Lat., consists of Entomostraca, which approximate to the Lerneae, in their external configuration, still more than the preceding subge- nera. There are but ten feet visible(3), mostly very short, and but slightly or nowise adapted to natation. Sometimes the body is nearly vermiform and cylindrical, the anterior {2) Anthosoma Smithii, Leach; Desmar., Consid., L, 3; Caligus imbricatus, R'lsso. (3)' There are probably two more, as in the preceding subgenera, but they are either indistinct or have such a peculiar form that they have not been recognized. PiECILOPODA. 153 segment being merely somewhat widened, and furnished with two projecting didactyle claws; sometimes, on account of two lateral expansions resembling lobes or wings behind the thorax, and of two posterior ovaries, it forms a small quadrilateral mass. This tribe is composed of two genera. In the first or the DicHELESTiUM, Hcrm., Jun. We observe a narrow elongated body, slightlydilated before, and composed of seven segments, the anterior of which — the thorax of Herm. — is wider than the others, rhomboidal, and formed of the head and a portion of the thorax united. It bears: 1, four short an- tennae, of which the laieral are filiform and consist of several joints, and the intermediate project like little arms and are quadri-articu- lated, the last joint terminating in a didactyle claw; 2, an inferior, membranous, and tubular siphon; 3, three kinds of deformed palpi — two multifidfeet? — on each side, placed on an eminence; 4, four pre- hensile feet, the two first of which consist of a thigh and leg ter- minated by various unequal and dcntated hooks, and the others of an enlarged thigh terminated by a small but stout nail. The second and third segments are almost lunulated, each bearing a pair of feet formed of a single joint, terminated by two kinds of toes, dentated at the end. To the fourth segment is attached another pair of feet, the fifth and last, but having the form of simple, oval, divergent, and immovable vesicles, which Hermann presumes are rather ovaries than feet. This segment, as well as the next, is nearly square. The sixth is much longer, and cylindrical. The seventh and last is three times shorter, almost orbicular, flattened and terminated by two small vesicles. The eyes are not distinct. Dichelestium siurionis, Herm., Jun. Mem. Apter. p. 125, V, 7, 8; Desmar., Consid. L, v. About seven lines long and one broad. The second segment is prolonged on each side into an obtuse papilla, and the four following are red in the middle, with whitish-yellow along the lateral margins. When viewed from above, the feet are not visible. This animal penetrates deeply into the skin and places itself on the osseous arches of the branchiae, but without, as it appears, intruding upon their combs. Twelve of them were taken by Hermann from a single fish. Of this number, two or three, perhaps males, were one third shorter than the others, and had a curved body; one of the twelve lived three days. They are constantly whirling about, and with considerable vivacity. By means of their frontal claws they are enabled to cling with great tenacity. Vol. hi.— U 154 CRUSTACEA. NicoTHOE, And. and Edw. These animals terminate the Crustacea, and are distinguished from all others of that class by their heteroclitical form. To the naked eye they seem nothing more than two lobes united in the form of a horse-shoe, which enclose two others. By the aid of glasses, how- ever, we discover that the two large lobes are formed by the great expansion of the sides of the thorax, which resemble wings, are almost oval and thrown behind; that the two others are external ovaries or clusters of eggs, analogous to those of a female Cyclops, and inserted, one on each side, into the base of the abdomen by means of a short pedicle; and that the body of the animal is com- posed of the following parts: 1, a distinct head furnished with two separate eyes; two short, setaceous, lateral antennae formed of ele- ven joints, each with a hair on the inner side; a mouth forming a circular aperture which acts as a cup, and accompanied on each side with — anterior feet — maxilliform appendages; 2, a thorax of four segments, with five pairs of feet beneath, the two anterior of which are terminated by a stout hook, and are bidentated on the inner side; the remaining eight being formed of one large joint, terminated by two nearly equal and cylindrical stems, each composed of three joints, and furnished with setae: 3, a pointed abdomen of five annuli, the first and largest of which gives origin to the oviferous sacs; the last is terminated by two long hairs. The lateral expansion merely appears to be an excessive development of the fourth and last ring of the thorax. Within we may perceive two kinds of entrails origi- nating from the median line of the body, which may be considered as caeca or divisions of the intestinal canal in a state of hernia. They are endowed with a very decided peristaltic motion. We have seen that the stomach of the Arguli also exhibits two caeca, which ramify in the wings of their shell, and it is possible that these thoracic ex- pansions of the Nicothoes may be two analogous lobes(l). Nicothoe asfaci^ Aud. and Edw. Ann. des Sc. Nat., 1826, XLIX, 1, 9. The only species known; it is about half a line long and three lines broad, the thoracic enlargement included. It is rose-coloured, paler on the oviferous sacs; the expansions yellowish. It adheres closely to the branchiae of the Lobster, and penetrates deeply between the filaments of those organs. It is only found in small numbers, and on a few individuals. All the Nicothoes observed by these two naturalists were furnished with ovaries; it is probable that previously to fixing themselves U) I» this case, the g'enns may be approximated to the preceding' one. P-ECILOPODA. 155 on the branchiae of the Lobster, and before their thoracic lobes have acquired their ordinary development, they can swim; that development, as is the case with the body of the Ixodes, may be the result of superabundant nutrition. TRILOBITES. According toBrongniartand various other naturalists, it is in the vicinity of the Limuli and other Entomostraca with numerous feet, that we should place these singular fossil ani- mals, originally confounded under the common name of Ento- inolithus paradoxus^ and now designated by that of Trilobites, of which an excellent monograph, enriched with good litho- graphic figures, has been published by that gentleman(l). By this hypothesis we have to admit as a positive or at least highly probable fact, the existence of locomotive organs, al- though, notwithstanding the most careful investigation, no vestige of them has been discovered (2). Presuming, on the contrary, that these animals were deprived of them, I thought that their natural position was in the neighbourhood of the Chitones, or rather that they constituted the original stock of the Articulata, being connected on the one hand with these latter Mollusca, and on the other with those first mentioned, and even with the Glomeres(3), to which some Trilobites, (1) M. Eudes Deslongchamps, professor of the University of Caen, Count Ra- soumowski, M. Dalman and other savans have since published new observations on these fossils. M. Victor Audouin, zealously advocating the opinion of Brong- niart, has contested that published by me, in which I approximate them to Chiton. The great difficulty was to prove the existence of feet, and this he has not done. The application of his theory of the thorax of Insects to the Trilobites, appears to me so much the more doubtful, as, according to my view of the matter, the first annuli of the abdomen of Insects alone represent the thorax of the Crustacea De- capoda. (2) M. Parkinson (Outlines of Oryctology) thinks he has perceived them, and suspeots that they are unguiculated. See also the Entomostradte granukuz Brongn., Trilob., Ill, 6, Ann. des So. Nat. tome XV. (3) First edition of the Regne Animal, tome III, p. 150, 151. There is no Branchiopoda known which can contract itself into the form of a ball. This cha- racter is peculiar to Typhis, Spharoma, Tylos, and Armadillo among the Crus- tacea; and among the class of apterous Insects to Glomens, a genus which is at the 156 CRUSTACEA. such as the Calymenes, appear to approximate, as well as to the Chitones, inasmuch as by contracting they could also be- come spherical. Since the publication of M. Brongniart's workj some naturalists have rejected his opinions and adopted mine, either wholly or in part; others still hesitate. Be this as it may, these animals appear to have been annihilated by some ancient revolution of our planet. The Trilobites, one hetcromorphous genus excepted, that of Agnostus, have, like the LimuH, a large anterior segment in the form of an almost semicircular or lunated shield, fol- lowed by from about twelve to twenty-two segments(l), all transversal except the last, and divided by two longitudinal sulci into three ranges of parts or lobes, whence their name of Trilobites(2). Some naturalists call them Entomostracites. head of that class, and which leaves between it and the latter Crustacea a consi- derable hiatus. The Calymenes, with respect to this contractility, evidently ap- proach these latter Insects, the Typhes and Sphxromae; but it does not appear that the posterior extremity of their body is provided with lateral natatory appen- dages, a negative character which would remove them from the Sphzeromi, but approximate them to Armadillo, and particularly to Tylos, where the superior part of the thoracic segments is divided into three. The study of a well pre- served specimen has convinced me that, like the Limuli, they had eyes placed against two prominences, and that the cornea was granulous or with facets. The non-existence of the superior antennse also indicates a new affinity between these same Trilobites and the Limuli. (1) The body of various Trilobites, and particularly of the Asaphi, seems to consist, exclusive of the shield, of twelve segments, well separated on the sides, and of another forming the post-abdomen, or a triangular or semi-lunar tail, whose divisions are superficial and do not cut its edges. In the Paradoxides, on the contrary, the lateral lobes terminate by well marked acute prolongations, and twenty-two of them can be distinctly counted. A species of Trilobite, men- tioned by Count Rasoumowski in his memoir on fossils, Ann. des Sc. Nat. June, 1826, pi. xxviii, ii, which he presumes should constitute a new genus, is, in this respect, very remarkable. Its lateral lobes form very long thongs or slips taper- ing to a point. The feet of the pupae of the Culices are elongated, flattened, inarticulated laminae terminated by threads and folded on the sides. They are in a rudimental state, and may be analogous to the lateral divisions of this species of Trilobite, allied to the Paradoxides. (2) The Squillae, and various Amphipodous and Isopodous Crustacea have also several of their segments trisected by two impressed and longitudinal lines; but these lines are nearer to the edges and do not form deep sulci. PiECILOPODA. 157 Agnostus, Brongn. The only genus where the body is semicircular or reniform. In all the other genera it is oval or elliptical, and exhibits the general cha- racters above mentioned. Calymene, Brongn. The Calymenes are distinguished from all other Trilobites, by the faculty of contracting their body into a ball, and in the same manner as Sphseroma, Armadillo, and Glomeris, that is, by approximating the two inferior extremities of the body. The shield, as broad as it is long, or broader, is furnished, as in the Asaphi and Ogygije, with two oculiform prominences. The segments do not project beyond the sides of the body, and are united throughout; the body is termi- nated posteriorly by a sort of triangular and elongated tail. In AsAPHus, Brongn. The oculiform tubercles seem to exhibit a sort of eye-lid, or are granulous; the species of tail which terminates the body posteriorly, is less elongated than in Calymene, and is either nearly semicircular, or in the form of a short triangle(l). In the Ogygia, Brongn. The shield is longer than it is broadj its posterior angles are extended into a kind of spine. The oculiform tubercles exhibit neither eye- lid nor granulations. The body is elliptical. Paradoxides, Brongn. The eye-like tubercles cease to exist, or are not apparent in this genus. The segments, or at least most of them, project beyond the sides of the body, and are free at their lateral extremity. Such are the characters of the five genera established by M. Alex- ander Brongniart, which may be arranged in three principal groups: the Reniformes — Agnostus; the Contractiles — Calymene; and the Extensi — Asaphus, Ogygia and Paradoxides, (1) In the ^sapkus Brongniarti, described and figured by M. E. Deslongchamps, the posterior angles of the shield, instead of being directed backwards as in the other species, are recurved. 158 CRUSTACEA. For a description of the species and their localities, we refer the reader to the excellent work of this celebrated naturalist, who in his labours upon the fossil Crustacea, properly so called, or universally admitted as such, has availed himself of the talents of one of his most distinguished pupils, M. Desmarest, frequently referred to by us, not only with respect to this particular part of the science, but in relation to his work on the living Crustacea. Different naturalists have proposed various generic sections of these fossils; but being restricted to general considerations, I have adopted those presented to us by the best work hitherto produced on the subject. 159 CLASS II. ARACHNIDES. The Arachnides, which compose the second class of articu- lated animals provided with movable feet, are, as well as the Crustacea, deprived of wings, are not subject to changes of form or do not experience any metamorphosis, simply casting their skin. Their sexual organs also are at a distance from the posterior extremity of the body, and situated at the base of the abdomen, those of several males excepted : but they differ from them as well as from Insects in several particulars. Like the latter, the surface of their body presents apertures or transverse fissures called stigmata{l)^ for the introduction of air, but they are few in number — eight at most, and usually but two — and confined to the inferior portion of the abdomen. Respiration is also effected either by means of air-branchise, fulfilling the functions of lungs, that are contained in sacs of which these stigmata are the apertures, or by radiated tra- cheaB(2). The visual organs merely consist of ocelli, which, when numerous, are variously grouped. The head, usually confounded with the thorax, in place of the antennae, has two articulated pieces in the form of small didactyle or mo- nodactyle chelse, improperly compared to the mandibles of Insects, and so denominated, moving in a contrary direction to the former, or from above downwards, still however co- operating in the business of manducation, and replaced in (1) A vague and improper appellation, for which we might substitute J5rt«u7?w»- totna, — air-mouth, — or spiraculum. (2) See general observations on Insects. 160 ARACHNIDES. the Arachnides, where the mouth has the form of a siphon or sucker, by two pointed blades which act as lancets(l). A kind of lip — labium, Fab. — or rather ligula, produced by a pectoral prolongation; two jaws formed by the radical joint of the first segment of two small legs or palpi (2), or by an ap- pendage or lobe of that same joint ; a part concealed under the mandibles, called langue sternale by Savigny — descrip- tion and figure of the Phalangium copticum — and composed of a projection in the form of a rostrum, produced by the union of a very small clypeus terminated by an extremely small tri- angular labrum, and of an inferior longitudinal carina, usually very hairy, are the parts, which, with the pieces termed mandibles, constitute with some modifications the mouth of most of the Arachnides. The pharynx(3) is placed before a sternal projection which has been considered as a lip, but which, from being placed directly behind the pharynx and having no palpi, is rather a ligula. The legs, like those of (1) Chelicerx, or forceps-aniennx: the evident result of the comparison between them and the intermediate antennae of various Crustacea, those of the PBCcilopoda particularly. It cannot then be said, strictly speaking, that the Arachnides are deprived of antennae, a negative character, which, previous to us, had been ex- clusively attributed to them. (2) They only differ from legs properly so called, by their tarsi, which are composed of a single joint, and are usually terminated by a small hook, resem- bling, in a word, the ordinary feet of the Crustacea. See our general observa- tions on the first order. These jaws and palpi appear to correspond to the pal- pigerous mandibles of the Decapoda and to the two anterior feet of tlie Limuli. In Phalangium, the four following legs have a maxillary appendage at their origin, so that these four appendages are analogous to the four jaws of the preceding animals. I had described these parts, long before the publication of Savigny's memoirs on the invertebrate animals, in a monograph of the species of this genus proper to France. From these and the preceding observations it is evi- dent that tlie composition of these animals is easily reduced to the same general type which characterizes all articulated animals with articulated feet. The Arach- nides are not then a sort of acephalous Crustacea, as stated by this savant, usually so exact in his anatomical observations, of which, unfortunately for the sciences, he has become the victim. (3) Although Savigny admits of two orifices, neither Straus nor myself can find but one; it must have been the eff'ect of an optical illusion, arising from the fact of his having only perceived the lateral extremities of the fissure, its middle being concealed by the tongue with which its anterior fiice is thickened in its mediate portion. ARACHNIDES. 161 insects, are commonly terminated by two hooks, and even sometimes by one niorcj and are all annexed to the thorax, or rather cephalo-thorax, which, except in a small number, is only formed of a single segment and is frequently intimately united to the abdomen. This latter part of the body is soft, or but slightly defended, in most of them. With respect to their nervous system, the Arachnides are greatly removed from the Crustacea and Insects; for if we ex- cept the Scorpions, which from the knots or joints forming their tail have some additional ganglions, the number of these enlargements of the two nervous cords is never more than 'three, and even in the latter, all counted, it never extends beyond seven. Most of the Arachnides feed on Insects which they either seize alive, or to which they adhere, abstracting their fluids by suction. Others are parasitical, and live on vertebrated animals. Some of them however are only found in flour, on cheese, and even on various vegetables. Those which live on other animals frequently multiply there to a great extent. Two of the legs, in some species, are only developed by a change of the tegument, and in general it is not until the fourth or fifth change of skin that these animals are capable of pro- pagation(l). Division of the Arachnides into orders. Some have pulmonary sacs(2), a heart with very distinct vessels, and six or eight simple eyes. They compose our first order, or that of the Pulmonari^. The others respire by trachesB, and have no organs of cir- (1) We have seen, according' to the observations of Jurine, Juh., that they only acquire this faculty after their sixth change. This fact is also applicable to the Lepidoptera, and probably to other insects that frequently cast their skin, for caterpillars usually change it four times before they enter into the state of a chry- salis which is a fifth. The insect does not become perfect until after another, so that it changes its skin six times. (2) Sacs containing air-branchije, or fulfilling the functions of lungs, and distin- guished by me from the latter by the name o{ pneumo-branchiae. ' Vol. III.— V 162 ARACHNIDES. culation, or if they have, the circulation is not complete. The trached^ are divided near their origin into various branches, and do not, as in Insects, form two trunks wliich run parallel to each other throughout the whole length of the body and receive air from various points by means of numerous stigmata. Here, but two, at most, are distinctly visible, and they are situated near the base of the abdomen(l). The number of simple eyes is at most but four. They constitute our second and last order, or that of the Tracheari^e. ORDER I. PULM0NARIiE(2). We here find a well marked circulating system and pulmo- nary sacs, always placed under the abdomen, announced ex- ternally by transverse openings or fissures (stigmata), of which there are sometimes eight, four on each side, and at others four, or even two. The number of simple eyes is from six to eight(3), while in the following order it never exceeds four, and is most generally but two ; sometimes they are hardly per- ceptible, or even annihilated. The organ of respiration is formed of little laminae. The heart is a large vessel which (1) The Pycnogonides exhibit no stigmata, and seem, in this respect, to approach the last of the Crustacea, such as Dichelestium, Cecrops, and other Siphonostomous Entomostraca. Savigny thinks they have a closer affinity to the Laemodipoda, from which, however, they are greatly removed, by the organization of the mouth as well as by their eyes and feet. We still believe, however, from the en- semble of their ehai-acters, that they rather belong to the class of Arachnides, and that they approximate particularly to Phalangium with which various authors have arranged them. We also think that they may respire by the surface of their skin. At all events, we must await the results of anatomical investigation, be- fore we can decide. (2) Unogata, Fab. (3) The Tessarops of Hafin., according to him, has but four eyes; I presume, however, that the lateral ones escaped his notice. See the subgenus Eresus. PULMONARIiG. 163 extends along the back, and gives off branches on each side and anteriorly(l). There are always eight legs. The head is always confounded with the thorax, and presents at its anterior superior extremity two mandibles — -so called by authors, the chelic.erse or antenne-pinces, Latr. — terminated by two fingers, one of which is movable, or by a single one resembling a hook or claw that is always movable(2). The mouth is composed of a labrum(3), of two palpi, sometimes resembling arms or claws, of the two or four jaws, formed, when there are but two, by the radical joint of these palpi, and moreover, when there are four, by the same joint of the first pair of feet, and of a ligula consisting of one or two pieces(4). If we base our arrangement on the progressive decrease of the number of pulmonary sacs and stigmata, the Scorpions where it is eight, while in the other Arachnides it amounts to but four or two, should form the first genus of this class, and consequently our family of the Pedipalpi should precede that of the Araneides(5). But the latter Arachnides ( 1 ) According- to Marsel de Serres,Memoire sur le Vaisseaii Dorsale des Insectes, the blood, in the Araneides and Scorpions, is first directed to the organs of respira- tion, and thence proceeds to various parts of the body through particular vessels. Judging-, however, from the affinity of these animals to the Crustacea, the circula- tion would seem to be effected in the contrary direction. See the Memoir of Treviranus on the Anatomy of Spiders and Scorpions. (2) These parts are formed of a first very large and ventricose joint, one of whose superior angles, when the chelee are didactyle, forms the fixed finger, and of a second joint, that which forms the opposite and movable finger or the hook, when tliere is but one finger. In the latter case, as with several of the Crustacea, I will employ the term claw. (3) See our general observations on the class. (4) That of the Scorpions appears to be composed of four pieces, forming an elongated and pointed triangle, directed forwards; the two lateral ones however are evidently formed by the first joint of the two anterior feet, and may be con- sidered as two jaws analogous to the first. We see by My gale, Scorpio, &c. that the palpi are divided into six joints, of which, in the other Araneides, the first or radical one, is anteriorly and internally dilated to form the maxilliform lobe. Even this lobe, in some species, is articulated at base, and thus becomes a maxillary appendage of this same joint. Exclusive of this joint, the palpus consists of but five, and such is the most usual mode of supputation. In the Scorpions the movable finger of the forceps, as in that of the Crustacea, forms the sixth joint. (5) In my Fam. Nat. du Regne Animal, 1 begin with the Pedipalpi. M. Leon Dufour also thinks that the Scorpions should come first. 164 ARACHNIDES. are in a manner insulated by their male organs of generation^ by the claw or hook of their frontal mandibles, by their pedi- culated abdomen and its spinning apparatus, and by their habits; besides this, the Scorpions appear to form a natural transition from the Arachnides Pulmonari* to the family of the Pseudo-Scorpionesj or the first of the following order. We will therefore commence, as we have said, with the Araneides or spinners. FAMILY I. ARANEIDES. This family is composed of the genus Auanea, Lin., or the Spiders. I'hey have palpi resembling little feet, without a forceps at the end, terminated at most in the females by a lit- tle hook, and the first joint of which, in the males, gives ori- gin to various and more or less complicated sexual appen- dages(l). Their frontal chelicerse (the mandibles of authors) are terminated by a movable hook, flexed inferiorly, under- neath which, and near its extremity, which is always pointed, is a little opening, that allows a passage to a venomous fluid contained in a gland of the preceding joint. There are never more than two jaws. The ligula consists of a single piece, is always external and situated between the jaws, and either more or less square, triangular or semicircular. The thorax(2) usually marked with a depression in the form of a V, indicating the space occupied by the head, consists of a single segment, (1) From all the observations that have been made on the mode of copulation of the Araneides, I am still inchned to believe that these appendages are the genital organs. I have vainly sought for. particular organs on the base of the abdomen of a large male Mygale preserved in spirits. We are not always to judge from analogy; for the sexual organs in the female Glomeris, Julus, and other Chilognatha, are situated near the mouth, a fact of which no second exam- ple is tol)e found. (2) The term cephalo-fhorax, would be more strict and proper; not being in use, however, I have thought it best to avoid it; neither will I employ that of corselet, although generally admitted, because, with respect to the Coleoptera, Orthoptera, &c. it only applies to the prothorax or first thoracic segment. PULMONARI-E. 165 posteriorly to which, by means of a short pedicle, is suspended a movable and usually soft abdomen, it is always furnished, under the anus, with from four to six closely approximated cylindrical or conical, articulated mammillae with fleshy ex- tremities, which are perforated with numberless small ori- fices(l ) for the passage of silky filaments of extreme tenuity proceeding from internal reservoirs. The legs, identical as to form, but of different sizes, are composed of seven joints, of which the two first form the hip, the third the thigh, the fourth(2) and fifth the tibia, and the two others the tarsus: the last is terminated by two hooks usually pectinated, and in se- veral by one more, Which is smaller and not dentated. The intestinal canal is straight, consisting of a first stomach com- posed of several sacs, and then of a second stomach or dilata- tion surrounded with silk. According to the observations of M. Leon Dufour — Ann. des Sc. Phys. VI — it occupies the greater part of the abdominal cavity, and is immediately en- veloped by the skin. It is of a pulpy consistence, and is form- ed of granules(3), whose individual excretory ducts unite in several hepatic canals, which pour the secreted matter into the alimentary tube. In the middle of its superior surface is a depressed line, where the heart is lodged, and which di- vides that organ into two equal lobes. Its form, like that of the abdomen, varies according to the species; thus in the Epeira sericea its contour is festooned. In this subgenus, as in the Lycosa tarentula^ its surface is covered with a whitish coat split into areolae, which, in several species, are easily perceived through the glabrous skin ; they may be seen obey- ing the impulse communicated to them by the systole and (1) These holes are pierced in the last segment, which is frequently retracted. If it be strongly compressed, very small mammillae, (at least in some species,) per- forated at the extremity, are protruded — they are the true fusi or spinning appa- ratus. Some naturalists think that the two smaller mammillse, situated in the middle of the four exterior ones, furnish no silk. (2) This joint or the first of the tibia is a kind of patella. {i) The liver of the Scorpions is composed of pyramidal and fasciculated lobules, a circumstance which seems to announce a more advanced degree of organization. 166 ARACHNIDES. diastole of the heart. Both sexes frequently eject from the anus an excrementitious fluid, part of which is milk-white, and the remainder black as ink. The nervous system is composed of a double cord occupy- ing the median line of the body, and of ganglions which dis- tribute nerves to the various organs. M. Dufour has not been able to determine tlie number and disposition of these gang- lions, but from the figure of this system given by Treviranus — Veber deninnern, bau des Arachniden, tab, V, fig. 45 — there are but two. The observations of the latter will also supply The v.ant of those relative to the organ of the circulation by M. Dufour, which, according to him, Appears to consist of a simple dorsal vessel, as well as with respect to the testes and spermatic vessels, on which he is totally silent. The dorsal region of the abdomen in several Araneides, those especially which are glabrous or but slightly pilose, ex- hibits depressed points varying both in number and arrange- ment. M. Dufour has ascertained that these little orbicular depressions are caused by the insertion of filiform muscles, which traverse the liver, and which he has also observed in the Scorpions. The one or two pairs of pulmonary sacs are indicated exter- nally by as many yellowish or whitish spots near the ventral base, and immediately after the segment which by means of a fleshy thread unites the abdomen with the thorax. Each pulmonary bursa is formed by the superposition of numerous, triangular, white, and extremely thin leaflets, which become confluent round the stigmata, and wiiose number exactly equals that of the pulmonary sacs. When there are four, a sort of fold or annular vestige found even in those where there are but two, and placed directly 'behind them, forms a line that separates the two pairs. The females have two very distinct ovaries, lodged in a spe- cies of capsule formed by the liver. In an unfecundated state they appear to be composed of a spongy, flaky kind of tissue, formed by the agglomeration of rounded, and scarcely visible corpuscles, which are the germs of eggs. As the results of PULMONARIiE. 167 fecundation become more apparent, the cluster formed by these ova(l) becomes less compact, and they are seen to be laterally inserted on several canals. Their great analogy to the ovaries of the Scorpions induces the same observer to pre- sume that they form meshes terminating in two distinct ovi- ducts, which open into a common vulva. The figure of the latter varies ; sometimes it is a longitudinal bilabiated slit, as in the Micrommata argelasia ; sometimes it is protected by an elongated operculum with a caudiform termination, as in the Epeira diadema; and at others resembles a tubercle. With respect to the simple eyes, or ocelli, he remarks, that they shine in darkness like those of Cats, and that the Araneides most probably enjoy the faculty both of nocturnal and diurnal vision. The abdomen becomes so putrid and decomposed after death, that its colours and even its form are soon destroyed. M. Dufour, by means of a rapid desiccation, the mode of which he points out, has succeeded in remedying this evil to a great degree. The silk, according to Reaumur, is first elaborated in two little reservoirs, shaped like tears of glass, placed obliquely, one on each side, at the base of six other reservoirs, resem- bling intestines, situated close to each other, flexed six or seven times, proceeding from a little beneath the origin of the abdomen, and terminating in the papilloe by a very slen- der thread. It is in these last mentioned vessels that the silk acquires a greater degree of firmness and other properties peculiar to it; they communicate with the preceding ones by branches, forming a number 6f geniculate turns, and then va- rious pieces of net-work(2). The newly spun filaments, when first drawn from the mammillae, are adhesive, and a certain degree of desiccation or evaporation is required to fit them for their destined purposes. When the temperature is propitious, (1) For their development and that of the fetus, see the admirable work of Herold, (2) See Treviramis, on the same subject. 168 ARACHNIDES. however, a single instant is sufficient, as the animal employs them the moment they escape from the apparatus. Those white and silky flocculi that may be observed floating about in spring and autumn in foggy weather,, vulgarly termed in France y?/5 de la Vict'ge, are certainly produced — as we have satisfactorily ascertained by tracing them to tlieir point of origin — by various young Araneides, those of the Epeirse and Thomisi particularly; they are mostly the larger threads which are intended to afford points of attachment to the radii of the web, or those that compose the chain, and which, becoming more ponderous by the access of moisture, sink, approach one another, and finally form little pellets: we frequently observe them collected near the web commenced by the Spider, and in which it resides. It is also very probable that many of these young animals not having as yet a sufficient supply of silk, limit their structure to throwing out simple threads. It is, I think, to the young Ly- cosae that we must attribute those which intersect the furrows of ploughed groiuids, whose numbers are rendered so appa- rent by the reflection of light after sunrise. By chemical ana- lysis, these Jils de la Vierge exhibit the same characters as the web of the spider: — they are not then formed in the atmo- sphere, as, for want of proper observation, exvisu, that cele- brated naturalist, M. Lamarck, has conjectured. Gloves and stockings have been made with this silk ; but it was found im- possible to apply the process on a large scale, and as it is sub- ject to many difficulties, is rather a matter of curiosity than utility. This substance, however, is of much greater impor- tance to the little animals in question. With it, the sedentary species, or those which do not roam abroad in search of their prey, WTave webs(l) of a more or less compact tissue, whose form and position vary according to the peculiar habits of each of them, and that are so many snares or traps, where the insects on which they feed become entangled, or are (1) Those of some exotic species are so strong, that small birds are entangled in them; they even oppose a certain degree of resistance to man. PULMONARI^. 169 taken. No sooner is one of them arrested there by the hooks of its tarsi, than the Spider, some times placed in the centre of his net, or at the bottom of his web, or at others lying in ambush in a peculiar domicil situated near and in one of the angles, rushes towards his victim and endeavours to pierce him with his murderous dart, distilling into the wound a prompt and mortal poison ; should the former resist too vigor- ously, or should it be dangerous to the latter to approach it, he retreats, waiting until it has either exhausted its powers by struggling, or become more entangled in the net; but should there be no cause of fear, he hastens to bind it by in- volving the body in his silken threads, with which it is some- times completely enveloped. Lister says that Spiders dart their threads in the same way that the Porcupine darts his quills, with this difference, how- ever, that in the latter, according to the popular belief, the spines are detached from the body, whereas in the former, these threads, though propelled to a considerable distance, always remain connected with it. The possibility of this has been denied. Be it as it may, we have seen threads issuing from the mammillae of several Thomisi form straight lines, and when the animals moved circularly, producing movable radii. A second use to which this silk is applied by all female Ara- neides, is in the construction of the sacs destined to contain their eggs. The texture and form of these sacs are variously modified, according to the habits of the race. They are usually spheroidal ; some of them resemble a cap or tymbal, others are placed on a pedicle, and some are claviform. They are sometimes partially enveloped with foreign bodies, such as earth, leaves, &c.; a finer material, or sort of tow or down, frequently surrounds the eggs in their interior, where they are free or agglutinated and more or less numerous. As they are voracious animals, the males, in order to avoid a surprise and to prevent themselves from falling victims to their pre- mature desires, approach their females in the nuptial season, with the greatest circumspection and mistrust. They cau- tiously and repeatedly touch them, and frequently for a long Vol. III.— W 170 ARACHNIDES. time before they yield to their wishes, and when this is the case they quickly and repeatedly apply the extremity of their palpi to tlie inferior surface of the abdomen, protruding at each time and as if by a spring, the fecundating organ con- tained in the button formed by the last joint of those palpi, and insinuate it into a sub -abdominal slit, near the base and between tlie respiratory orifices; after a moment's interval the same act is repeatedly performed. Such is the mode of co- pulation of a small number of species belonging to the Orbi- tekc. It is impossible to avoid feeling the most lively interest in reading what has been written upon this subject by that learned naturalist, who of all others has most profoundly stu- died these animals, the celebrated VValckenaer, member of the Acad, des Inscriptions et Belles-lettres. The apparatus of the male organs of generation, or at least of what are consi- dered as such, is usually highly complicated and very various; it consists of scaly pieces, more or less hooked and irregular, and of a white fleshy body, on which sanguineous looking vessels are sometimes perceptible, which is considered as the fecundating organ, properly so called ; but in the Arachnides with four pulmonary sacs, and in some belonging to the divi- sion where there are but two, the last joint of the palpi of the males only exhibits a single horny piece in the form of a hook or ear- picker, without the smallest visible opening. Although MuUer and others were mistaken when they placed the male organs of certain Entomostraca upon two of their antennae, it is very certain that the parts considered as analogous to them in the Araneides, are very different from those observed on the antennae of those Crustacea, and that if we refuse to admit of their exercising this function, it is impossible to con- ceive of their use(l). According to the experiments of Audebert, who has given us a history of the Monkeys worthy of the talents of that great painter, it is certain that a single fecundation is sufficient for several successive generations, but that with them, as with (Ij They must at nil events be ofgans of excitation. PULMONARIiE. 171 all Insects and other analogous classes, the ova are sterile without a union of the sexes. Their nuptial season in France lasts from the latter end of summer till the beginning of Octo- ber. The ova first laid are frequently hatched before the ter- mination of autumn : the others remain in statu quo during the winter. The females of certain species of Lycosa have been observed to tear open the egg-sac when the young ones were about to issue from the ovum. The latter' then mount on the back of their mother, where they remain some time. Other female Araneides carry their cocoons under the abdomen, or remain near them and Watch them. The two posterior feet of some of the young ones are not developed until several days after they have been hatched. Some, during the same period, live together, and appear to spin in common. Their colour- ing is then more uniform, and the young naturalist may easily err in multiplying their species. One of our collabo- rators for the Encyclopedic Methodique, M. A. Lepelletier of Saint-Fargeau, has observed that these animals^, as well as the Crustacea, possess the faculty of reproducing a lost limb. I have ascertained that a single wound from a moderate sized Araneid will kill our common Fly in a few minutes. It is also certain that the bite of those large Araneides of South America, which are there called Crab-Spiders, and are placed by us in the genus Mygale, kills the smaller vertebrated ani- mals, such as Humming-Birds, Pigeons, &c., and produces a violent fever in Man ; the sting of some species in the south of France has even occasionally proved fatal. We may therefore, without believing all the fabulous stories of Baglivi and others respecting the bite of the Tarantula, mistrust the Araneides, and particularly the larger ones. Various insects of the genus Sphex, Lin., seize upon these Spiders, pierce them with their sting, and transport them into holes where they have deposited their eggs, as a source of food for their young. Most of them perish in winter, but there are some which live several years — such are the My- gales, the Lycosa, and probably several others. Although Pliny states that the genus Phalangium is unknown in Italy, 172 ARACHNIDES. we still presume that these latter Araneides and other large species which weave no web, as also the Galeodes and Solpu- gsE, are the animals they collectively designated by that name, and of which they distinguished several species. Such also was the opinion of MoufTet, who, in his Theat. Insect., p. 219, has figured a Lycosa or Mygale, of the island of Can- dia, as a species of Phalangium. Lister was the first and most successful observer of the Spiders, whose habits he was enabled to study; those of Great Britain laid the foundations of a natural arrangement, of which most of those that have been since published are mere modi- fications. The more recent discovery of species peculiar to hot climates, such as the Araignee magonne described by the abbe Sauvages, and some others, the use of the organs of man- ducation introduced into the system by Fabricius, a more exact study of the general disposition of the eyes, and of their respective sizes, with that of the relative length of the legs, have all contributed to extend this classification. Walck- enaer has entered into the most minute of these details, and it would be a difiicult matter to discover a species that could not find its place in some one of his divisions. One character, however, existed, the application of which had not been made general : I allude to the presence or absence of the third ter- minal hook of the tarsi. Savigny, so far as this is concerned, has given us a new method, of which, however, I have only seen a simple sketch(l). (1) See Walck., Faun. Franc, note to genus .4/te. We knew nothing- of the observations of M. Savigny on the Spiders, which ac- company the plates of Nat. Hist, of the great work on Egypt, until long after our article relative to the same animals was printed. That gentleman — Hist. Nat. ut sup. — establishes the following genera in the family of the Araneides: 1. Ariadne, near that of Segestria, having but six eyes, of which the two intermediate posterior ones are further forwards; — 2. Lachesis, near Drassus, but with the hooks of the Chelicerse, (/orcjpu/es, Savign.,) very small; — 3. ERiGOif E, also allied to Drassus as well as to Clubiona; thorax very high before; second joint of the palpi spinous, and dilated into angle or tooth at the extremity; — 4. Hersilia, allied to Agelena and Theridion of Walckenaer; feet long and slender, the superior nails bidentate; eyes united on an eminence, ar- ranged in two transverse lines, and curved backwards; two very long fusi PULMONART^. 173 M. Leon Dufour, who has published many excellent me- moirs on the anatomy of Insects, who has especially studied those of Valencia, among which he has detected several new species, and to whose labours the science of Botany is not less indebted, has paid particular attention to the respiratory or- gans of spiders, and it is from him that we have taken our divisions, which consist of those that have four pulmonary sacs — with as many external stigmata, two on each side, and closely approximated — and of such as have but two(l). The first, which embraces the order of the Theraphosse of Walck- enaer, and some other genera of the one he collectively desig- nates by the name of Spiders, acccording to our method form but the single genus Mygale. Their eyes always situated at the anterior extremity of the thorax, and usually, closely approximated; feet and chelicerse robust; co- pulating organs of the males always salient and frequently very simple. Most of them have but .four fusi, of which the two late- ral or external, situated somewhat above the others, are longest, and consist of three segments, exclusive of the prominence that forms their peduncle. They weave silken tubes in which they reside, and which they conceal either in holes excavated by them for that purpose, or under stones, bark of trees, or between leaves. The Theraphosae of Walckenaer will form a first division, the characters of which are: 1. Four(2) fusi, of which the two that are intermediate and inferior, are usually very short, and the two that are exterior, very salient; the hooks of the chelae doubled un- derneath, or along their carina or inferior edge, and not on the inner side of their internal face, or upon it; eight eyes always, usu- ally grouped on a little eminence, three on each side, forming a foi-ming a tail; — 5. Auachne, which does not appear to us to differ from Ange- lena; — 6. Argtopes, Epeirae wliose anterior; lateral eyes are much smaller than the others; — 7- Esro, fifth family of the Theridion, Walck. ; — S. Octale, second family of the Dolomedes, Id. (1) Sectionof the Territelae of our first edition. (2) 1 have perceived, in the Atypi, vestiges of two other mammillae, those which, in the Spiders of the ensuing division, are placed between the four exterior ones, and are, there, very visible; as they are here but scarcely apparent, I have not thought it requisite to notice them. 174 ARACHNIDES. reversed triangle, and the two superior ones approximated; the remaining two arranged transversely between the preceding. The fourth pair of legs arc the longest, and then the first; the third is the shortest. Here the palpi are inserted into the superior extremity of the jaws; so that they appear to consist of six joints, the first of which, narrow and elongated, with the internal angle of the superior extre- mity salient, fulfils the functions of a jaw. The ligula is always small and nearly square. The last joint of the palpi of the males is short, has the form of a button, and bears the organs of genera- tion at its extremity. The two anlerior legs of the same sex have a stout spine or spur at their inferior extremity. Such are the cha- racters of the Mygale, Walck. , Or the true Mygales. In some of them we find no transverse series of horny and movable spines or points, resembling the teeth of a rake, at the superior extremity of their chelicerse immediately above the insertion of the claw or hook which terminates them. The hairs which decorate the under part of their tarsi, form a thick and broad brush, projecting beyond the hooks, and usually conceal- ing them. The male organs of generation consist of a single scaly piece, terminated by an entire point, or neither emarginated nor divided; sometimes it is formed like an ear-pick — M. de la Blond, Lat. — usually, however, it is globular inferiorly, then becomes nar- row, terminates in a point, and forms a kind of arcuated hook. This division is composed of the largest species of the family, some of which, when at rest, cover a circular space of from six to seven inches in diameter; they sometimes seize upon Humming- birds. They establish their domicil in the clefis of trees, under the bark, in the fissures of rocks, or on the surface of leaves of various plants. The cell of the Mygale avicularia has the form of a tube, narrowed into a point at its posterior extremity. It consists of a Avhite web, of a close, very fine texture, semi-diaphanous, and resem- bling muslin. One of them, presented to me by M. Goudot, when unrolled, was about two decimetres in length, and six centimetres in breadth, measured across its greatest transversal diameter. The cocoon of the same species was of the figure and size of a large walnut. Its envelope, consisting of the same material as that of its domicil, was formed of three layers. It appears that the young arc hatched in it, and undergo their first change of tegument there. PULMONARI^. 175 The naturalist just mentioned, stated to me, that he had taken a hundred of them from a single cocoon(l). This Mygale — Aranea avicularia, L.; KU'em. Insect. XI, and XII, the male — is about an inch and a half long, blackish, and , extremely hairy; the extremity of the feet and palpi, and the inferior pili of the mouth reddish. The genital organ of the male is hollow at base, and terminates in an elongated and very acute point. South America and the Antilles produce other species, called by the French colonists Araign^es-crahes. Their bite is reputed to be dangerous. A very large species — M.fasciata; Seb., Mus., I, Ixix, i; Walck., Hist, of Spiders, IV, i, the female — is also found in the East Indies. A species, nearly as large as the avicularia, inhabits the Cape of Good Hope. Another of the same division — M. Valcntina — was discovered in the sandy and desert districts of Moxenta, in Spain, by M. Dufour, who has described and figured it in the Ann. of the Phys. Sciences, Brussels, vol. V. Walckenaer has also described a second species from that peninsula which has two prominences above its respiratory organs. These two latter species form a parti- cular group, characterized by the hooks of the tarsi, which are salient or exposed(2). In the following Mygales(3), the superior extremity of the first joint of the chelicerae presents a series of spines, articulated and movable at base — according to the observations of Dufour — and forming a sort of rake. The tarsi are less pilose underneath than in the preceding divi- sion, and their hooks are always exposed. The males of one species, the only ones I have seen, have more complicated organs of gene- ration than those of the preceding division. The principal and scaly piece incloses a peculiar, semiglobular body, terminating in a bifid point, in an inferior cavity(4). These species, in the dry and mountain districts of the south of Europe and of some other countries, excavate subterraneous galle- (1) See my memoir on the habits of the Avicularia in the Ann. du Mus. d'Hist. Nat. VIII, p. 456. (2) For details concerning' these and the following species, as well as for the other genera of this family, see the corresponding articles in the Nouv. Diet. d'dist. Nat., where we treat of them at length. (3) The genus Ctexiza, Lat., Fam. Nat. du Ragne Animal. (4) On this point I am contradicted by M. Dufour. I was compelled again to examine the fact, and have convinced myself that 1 was not mistaken. It is poss- ible the specimens he examined did not present this character. 176 ARACHNIDES. ries, which are frequently two feet in depth, and so extremely tortu- ous, that, according to Dufour, it is frequently impossible to trace them. At the mouth, they construct a movable operculum with earth and silk, fixed by a hinge, which, from its form, nicely adjusted to the aperture, its inclination, its weight, and the superior position of the hinge, spontaneously shuts, and completely closes the entrance of their habitation, forming a kind of trap-door, which is scarcely distinguishable from the surrounding eartlf. Its inner surface is lined with a layer of silk, to which the animal clings, in order to keep its door shut and prevent intruders from opening it. If it be slightly raised, it is a sure indication that the owner is within. Unearthed by laying open the gallery front of the entrance, it be- comes stupified, and allows itself to be captured without resistance. A silken tube, or the nest properly so called, lines the inside of the gallery. M. Dufour thinks that the males never excavate. Inde- pendently of his having found them under stones only, they do not seem to him so well prepared with organs adapted to such work(l). Without deciding upon this point, we presume, with him, that the Mygale carminans of France — Nouv. Diet. d'Hist. Nat., art. My- GALE — is merely the male of the following species: Walckenaer, however, doubts it. 31. caementaria, Lat.; Araign^e magonne, Sauvag., Hist, de I'Acad. des Sc, 1758, p. 26: AraignSe mineuse^ Dorthfes., Trans, Lin. Soc. II, 17, 8; Walck., Hist, des Aran., fasc. Ill, x; Faun. Fran9., Arach., II, 4; Dufour, Ann. des Sc. Phys., V, Ixxiii, 5. The female Mason Spider, as it is called, is about eight lines in length, of a reddish colour, verging on a brown more or less deepj edges of the thorax paler. The chelicerae are blackish, each one furnished abo\e, near the articulation of the hook, with five points, of which the internal is the shortest. The abdomen is of a mouse-grey, with streaks of a darker hue. The first joint of all the tarsi is furnished with small spines. The hooks of the last have a spur at their base, and a double range of acute teeth. The mammillae are but slightly prominent. According to Dufour — Ann. des Sc. Phys,, V, Ixxiii, 4 — the supposed male, of which I have made a species, 31. cardeicse, differs from the preceding individual in the greater length of its feet, in the hooks of the tarsi, which are twice the number of the other, but have no spurs, and in the diminibhed length of its mammillae. A more apparent character may be found in the (1) See his excellent memoir entitled, "Observations sur quelques Arachnides Quadripulmonaires." PULMONARI^. 177 stout spine, which terminates, inferiorly, the two anterior tibiae. This Mygale is found in the southern departments of France situated on the borders of the Mediterranean, in Spain, 8cc. M /orfi'ms, Walck. , Faun. Fran9., Arach., II, 1, 2;M. Saii- vagesii, Dufour, Ann. des Sc. Phys., V, Ixxiii, 3; Aranea Sau- vagesii, Ross. The female is somewhat larger than that of the preceding species, and of a light reddish-brown, without spots. The exterior fusi are long. The four anterior tarsi are alone furnished with small spines; all have a spur at the end, and their hooks have but a single tooth, situated at their base. The chelicerse are stouter and more bent than those of the Caementaria; the teeth of the rake are rather more numerous, and there are two ranges of teeth under the first joint. The male is unknown. This species is found in Tuscany and Cor- sica. There is a small clod of earth in the Museum d'Hist. Nat. of Paris, in which are four of its nests, forming a regular quadrilateral figure. M. Lefevre, who has made so many sacrifices to the science of Entomology, has discovered a new species of Mygale in Sicily, the entire body of which is of a blackish brown. The extremity of the anterior tibiae of the male does not exhibit that stout spine which appears to be peculiar to individuals of the same sex, in the other Mygales. Another species is found in Jamaica — M. nidukms — figured, together with its nest, by Brown in his Nat. Hist, of Jamaica, pi. xliv, 3. There, the palpi are inserted into an inferior dilatation of the ex- ternal side of the jaws, and consist of but five joints. The ligula, at first very small — Atypus — lengthens, and then advances between the jaws, and this character becomes general. The last joint of the palpi, in both sexes, is elongated, and pointed near the end. There is no spur to the extremity of the anterior tibiae of the males. Atypus, Lat. — Oletera, Walck. The Atypi have a very small ligula almost covered by the internal portion of the base of the jaws, and closely approximated eyes grouped on a tubercle. Atypus Sulzeri,- Lat., Gener. Crust, et Insect., I, v, 2, the male; Dufour, Ann. des Sc. Phys., V, Ixxiii, 6; Arnnea picea, Sulz.; OUtere atype, Walck., Faun. Fran9., Arach., II, 3. Body entirely blackish, and about eight lines in length. The thorax is nearly square, depressed posteriorly, inflated, widened, and broadly truncated anteriorly, presenting an appearance very Vol. III.— X 178 ARACHNIDES. different fiom ihai uT the same part in ihc Mygales. The che- licei'tE are very sloul, and underneath the claw and at its liasc is a little eminence resembling a tooth. The last joint of the palpi of the male is pointed at the end. From the genital organ arises, inferiorly, a little squamous sQmi-diaphanous piece, •widened and unequally bidcntated at the end, with a small seta or cirrus at one of its extremities. This species excavates a cylindrical gallery in sloping grounds covered with grass; in this gallery, seven or eight inches in length, horizontal at first and then inclined, it weaves a tube of white silk of the same form and dimensions. The cocoon is fastened with silk by both ends to ihe bottom of the gallery. It is found in the environs of Paris and Bourdeaux; M. Basoches has observed a variety near Seez, which is always of a light brown. M. Milbert has discovered another species — Alypus rujipes — near Philadelphia, which is entirely black, with fulvous feet. Eriodon, Lat. — Missulenu, Walck. The Eriodons differ from the Atypi in their elongated, narrow ligula advancing between their jaws, and in their eyes, which are scattered over the anterior part of the thorax. The only species known — Eriodon occatoriua, Lat.; Missithna occaloria, Walck., Tai)l. des Aran. pi. IT, ii, 12 — is an inch long, blackish, and peculiar to New Holland, where it was discovered by MM. Pc'ron and Lesueur(l). In our second and last division of the quadripulmonary Spiders or Mygales, we find characters pommon to Eriodon, such as the ligula being prolonged between the jaws, and the palpi consisting of five joints; but the claws of the chelicerae are folded over their inner face, there are six fusi, their first pair of legs is the longest and not the fourth, and the third is always the shortest. Some of them have but six eyes. The number of pulmonary sacs will not allow us to remove the subgenera of this division from the preceding ones, and as they conduct us to Drassus, Clotho, and Segestria, sub- genera with but two pulmonary sacs, the natural order will not per- (1) In the first memoir of M. Dalman upon the Insects found in amber, that celebrated naturalist mentions (p. 25) a Spider which, it appeared to him, should be made the type of a new genus (Chalinura). The eyes are placed on a very high anterior tubercle, four of them, of which the two anterior are very large and ap- proximated, occupying the centre. Tbe external fusi are much elongated. From these characters it would seem that tliis sjiider approaches Mygale or some other analogous genus. PULMONARIiE. 179 mit us to pass from the Mygales to the Lycos« and other hunting or wandering Spiders. The Mygales are true tapissieres — or true spiders which line their galleries with silk — and in fact, it was in this division that the Aranea avicularia of Linnaeus was formerly placed. This second division comprises the two following subgenera. Dysdera, Lat. But six eyes arranged in the figure of a horse-shoe, the opening in front; the chelicerse very stout and projecting; jaws straight and dilated at the insertion of the palpi(l). FiLISTATA, Lat. Eight eyes grouped on a little eminence at the anterior extremity of the thorax; the cheliceras small; the jaws arcuated on the outer side, and surrounding the ligula(2). We now puss to Araneides with but one pair of pulmonary sacs, and as many stigmata. They all have palpi formed of five joints, inserted into the external side of the jaws near their base, and most frequently in a sinus; a ligula extending between them, either nearly square, ^riangular or semicircular, and six fusi at the anus. The last joint of the palpi, in the males, is more or less ovoid, and usually encloses, in an excavation, a complicated and varied organ of copu- lation; it is rarely — Sege.stria — exposed. With the exception of a few species, which enter into the genus Mygale, they compose that of Aranea, Lin. — Jlraneus of some authors. A first division will comprehend the AranejE Sedentari^, or seden- tary spiders. They make webs, or throw out threads to ensnare their prey, and always remain in these traps, or their vicinity, as well as near their eggs. Their eyes are approximated anteriorly and are sometimes eight in number, of which four or two are in the middle and two or three on each side, and sometimes six. Some, which, from the circumstance of their always moving for- wards, we term the Rectigrad^, weave webs and are stationary; (1) Dysdera eryihrina., Lat.; Walck'"., Tab. des Aran., V, 49, 50; Dufour, Ann. des Sc. Phys. V, Ixxili, 7; Aranea rufipes. Fab.; — Dysdera parvula, Dufour, lb. (2) Filistata bicolor, Lat.; Walck, Faun. Franc, Arach., VI, 1 — 3. A moderate sized species is found at Guadaloupe, the male of which has long and slender legs, curved palpi, with the genital organs situated. at the extremity of the last joint, and terminated by a slender arlR arcuated, or falciform hook. 180 ARACHNIDES. their legs are elevated wlicii at rest; sometimes the two first and two last are the longest, and at others those of the two anterior pairs, or the fourth and the third. The general arrangement of the eyes does not form the segment of a circle or a crescent. They may be divided into three sections: the first, or that of the Tubitelae, has cylindrical fusi approximated into a fasciculus di- rected backwards; the legs are robust, the two first or the two last, and vice versa, longest in some, and the whole eight nearly equal in others. We will commence with two subgenera, which, with respect to the jaws that describe a circle round the ligula, approach the Filisiatae, and are removed from those that follow. Clotho, Walck. — Uroctea, Dufour. A singular subgenus. The chtflicerae are very small, can sepa- rate but little — thereby approximating this subgenus to the last — and are not indented; very small hooks; the shortness of the body and length of the legs produce a resemblance to the Crab-Spiders or Thomisi. The relative length of these organs differs but little; the fourth pair, and then the preceding one are merely somewhat longer than the first; the tarsi, only, are furnished with spines. #The eyes are further from the anterior margin of the thorax than in the fol- lowing subgenus, and aie approximated and arranged as in the genus Mygale of Walckeiiaer; three on each side form a reversed triangle; the two others form a transverse line in the space comprised between the two triangles. The jaws and the ligula are proportiona- bly smaller than those of the same subgenus; a short projection or slight dilatation on the external side of the jaws, gives insertion to the palpi; the jaws terminate in a point; the ligula is triangular and not nearly oval as in Drassus. The two superior or most lateral fusi are long, but what, according to Dufour, particularly charac- terizes his Urocteae or our Clothos, is, that there are two pecti- niform valv*s which open and shut at the will of the animal(l), in place of the two intermediate fusi. But a single species is known, the Uroctea 5-maculata^ Du- four, Ann. des Sc. Phys., V, Ixxvi, 1; Clotho Durandii^ Lat. (1) I have seen, in a well preserved specimen, six fusi, of which the two superior were much the longest and terminated by an elongated joint, forming an elliptical lamina, and the other four small, the inferior ones particularly, and ar- ranged in a square. The anus, placed under a little membranous projection resembling a clypeus, was furnished on each 'side with a pencil of retractile hairs. These pencils are the parts named by Dufour pectiniform valves, and are distinct from the two intermediate fusi, which are conceded by the two inferior ones. PULMONARIiE. 181 The body is five lines in length, of a fine chesnut colour; abdo- men black; five small, round, yellowish spots above, four of which are arranged transversely in pairs, and the last or fifth posterior; legs hairy. It is evident from the plates of the great work on Egypt, that M. Savigny found it in that country, and proposed forming a new genus with it. Count Dejean brought it from Dalmatia; and Schreiber, director of the Imperial Mu- seum of Vienna, has sent me specimens captured in the same country. M. Dufour also found it in the mountains of Nar- bonne, in the Pyrennees and among the rocks of Catalonia. To this latter naturalist we are indebted not only for our know- ledge of the external characters of this spider, but for many curious observations relative to its habits. " She constructs," says" he, " a shell resembling a calotte or patella an inch in diameter, on the under surface of larg« stones or in the fissures of rocks. Its contour presents seven or eight emarginations, the angles of which are alone attached to the stone by silken fasciculi, the margin being free. This singular tent is admira- bly woven. The exterior resembles the very finest taffeta, formed, according to the age of the animal, of a greater or less number of layers. Thus, when the young Uroctea first com- mences her establishment, she merely forms two webs between which she seeks for shelter. Subsequently, and I believe at each change of tegument, she adds a certain number of layers. Finally, when the nuptial season has arrived, she lines an apart- ment with a softer and more downy material which is to en- close the sac of eggs and young ones. Although the exterior shell is more or less soiled by foreign bodies which serve to conceal it, the chamber of the industrious architect is always extremely neat and clean. There are four, five, or six egg- pouches or sacculi in each domicil; they are lenticular, more than four lines in diameter, and formed of a snow-white taffeta lined with the softest down. The ova are not produced till the latter end of December or the beginning of January; the young are to be protected from the rigour of winter and the incursions of enemie's-^all is prepared; the receptacle of this precious de- posit is separated from the web that adheres to the stone by soft down, and from the external calptte by the various layers I have mentioned. Some of the emarginations in the edge of the pavilion are completely closed by the continuity of the web, the edges of the remainder are merely laid on each other, so "that by raising them up, the animal can issue from its tent or enter it, at pleasure. When the Uroctea leaves her habitation for the chase, she has nothing to fear, she only possesses the 182 AllACHNIDES. secret of the impenetrable emargxnation, and has the key to those which'alone aflford an entrance. When her offspring are able to provide for themselves, they leave their native dwelling, to establish elsewhere their individual habitations, while the mother returns to it and dies — it is thus her cradle and her tomb." DuAssus, Walck. The Drassi differ from Clotho in several characters. Their che- licerae are robust, projecting and denlated beneath; their jaws are ob- liquely truncated at the extremity, and the ligula forms an inferiorly truncated oval, or an elongated curvilinear triangle; the eyes are nearer to the anterior margin of the thorax, and the line formed by the four posterior ones is longer than th^ anterior, or extends beyond it on the sides. There is but little difference in the proportions of the fusi, and we do not observe between them the two pectini- form valves peculiar to Clotho. Finally, the fourth pair of legs, and then the first, are manifestly longer than the others. The tibise and first joint of the tarsi are armed with spines. These Spiders live under stones, in the fissures of walls, and on leaves; they construct their cells with an extremely white silk. The cocoons of some are orbicular and flattened, and consist of two valves laid one on the other. M. Walckenaer distributes the Drassi into three families, according to the direction and approximation of the lines formed by the eyes, and tlie greater or- less dilatation of the middle of the jaws. The species which lie calls viridissimus, Hist, des Aran, fascic, IV, 9, and which alone composes his third division, weaves a fine, white, transparent web on the surface of a leaf; under this web it seeks for shelter. 1 have sometimes observed a similar web on the leaf of the Pear-tree, but the margin was angular and resembling a tent, like that of the Clotho, beneath which was the cocoon. It is, I presume, the work of this species of Drassus, and proves the analogy of this subgenus wiih the pre- ceding one. M. Leon Dufour, Ann. des Sc. Phys., VI, xcv, 1, has given a very complete description of a species of Dras- sus — D. segestriformis — found by him under stones in the highest Pyrennees,and never beneath the Alpine region. It is one of the largest of this subgenus, and appears to me to be closely allied to my mdanogaster, which I believe to be the B. lucifugus of Walckenaer, Schaeff. Icon. CI, 7. One of the prettiest species, which is very commonly observed running along the ground in the vicinity of Paris, is the D. relucens. It is small, and almost cylindrical, with a fulvous PULMONARI^. ■ 183 thorax, invested with a purple silky down; the abdomen is a mixture of blue, red, and green, with metallic reflections, and marked by two transverse and golden lines, of which the ante- rior is arcuated. Four golden dots are sometimes observed on it(l). In the other Tubitelas the jaws do not surround the ligula; their external side is dilated inferiorly beneath the origin of the palpi. Some have but six eyes, four of which are anterior, and form a transverse line, and the two others posterior, situated, one on each side, behind the two lateral ones of the preceding line. Such is the essential character of the Segestria, Lat. The ligula is elongated and almost square. The first pair of legs, and then the second, is the longest; the third is the shortest. These spiders construct long, silky, cylindrical tubes in the chinks and crevices of old walls, which they inhabit; their first pairs of legs are always directed forwards,, and diverging threads border the external entrance of their domicil, forming a net for ensnaring Insects. The genital organ of the S. perjida — Aranea florentina, Ross., Faun. Etrusc, XIX, 3— a large black species with green chelicerse, which, is not rare in France, is shaped like a tear, or is ovoido-conical, very acute at the end, entirely salient, and red(2). The remaining Tubitelae have eight eyes. On account of the dif- ference in the site of their habitations, we may divide them into the terrestrial and the aquatic. Although the last family of the Ara- neides of Walckenaer (his Naiades) is composed of these latter, they are so closely allied to the other Tubitelse, that notwithstanding this disparity of habits they must be placed together. In those which are terrestrial, the ligula is almost sq'uare, or but very slightly narrowed, with a very obtuse or truncated summit; the jaws are straight, or nearly so, and more or less dilated towards the extremity; the two eyes of each lateral extremity of the ocular group are generally separated from each other, or at least are geminate and placed on a particular eminence like those of the aquatic Tubitelae. Clubiona, Lat. This subgenus is only distinguished from the following one by (1) For the other species, see Faun. Paris., Walck., andTabl. dcs Aran., Id. (2) Add the Seg, aenocuhta, "W^alck., Hist, des Aran., V, vii; Jlranca senocuhiia, : Desr 184 ARACHNIDES. the nearly equal length of the exterior fusi, and by the straight- ness of the line formed by the four anterior eyes. The Clubionae construct silky tubes under stones, in chinks of walls, or between leaves. Their cocoons are globular(l). Aranea. The true Aranese, which we at first designated by the generic ap- pellation of Tegenaria, retained by Walckenaer, and to which we add his Angelenae and Nyssi, have their two superior fusi much longer than the others, and their four anterior eyes arranged in a line posteriorly arcuated or forming a curve. They construct, in our houses, in the angles of walls, on plants, hedges, along the roads, in the earth, and under stones, a large and nearly horizontal web, at the upper part of which is a tube where they remain motionless(2). Then follow the Naiades of Walckenaer, or our aquatic Tubitelae, which form the Argyroneta, Lat. The jaws are inclined on the ligula, which is triangular. The two eyes of each lateral extremity of the ocular group are closely approximated and placed on a particular eminencej the four others form a quadrilateral. Argyroneta aquatica; Jiranea aquatica, L., Geoff., Deg. Blackish brown, the abdomen darker; silky; four depressed points on the back. It is found on the stagnant waters of Eu- rope, where it swims with the abdomen enclosed in a bubble of air; it forms an oval cell, filled with air, and lined with silk, from which various threads extend to the surrounding plants. Here it lies in wait for its prey, deposits its cocoon, which it carefully watches, and encloses itself to pass the winter. In the second section of the sedentary and rectigrade spiders, that of the IxEquiTEL^, the external papillae are nearly conical, project but little, are convergent, and form a rosette; the legs are very slen- der. The jaws incline over the lip, and become narrower at their superior extremity, or at least do not sensibly widen. Most of them have the first pair of legs longest, and then the (1) Jiranea holosericea, L. ; Degeerj Fab. ; Walck., Hist, des Aran. IV, iii, fem. ; — Aranea atrosc. Deg., Fab.; List, Aran-, XXI, 21; Albin, Aran., X, 48, and XVII, 82. See also Tab. des Aran., and the Faun. Paris., Walckenaer. (2) Aranea domestica, L., Deg., Fab.; Clerck., Aran. Suec, pi. ii, tab. ix; — Tegeneria civilis, Walck., Hist, des Aran., V, \ ,— Aranea Uibyrinthica, L., Fab. ; Clerck, Aran., Suec. pi. ii, tab. viii. See the Tab. des Aran., Walck. PULMONAUIyE. 185 fourth. The abdomen is more voluminous, softer, and more colour- ed than in the preceding tribes. Their webs form an irregular net composed of threads which cross each other in every direction and on several planes. They lie in wait for their prey, display much anxiety for the preservation of their eggs, and never abandon them till they are hatched. They are short-lived. In some, the first pair of legs, and then the fourth, are the longest. SCYTODES, Lat. But six eyes arranged in pairs. According to Dufour, the hooks of their tarsi are inserted into a supplementary joint. Two species are known, one of which, the ^/joracJca( 1) in- habits houses in Europe, and the other, la blonde, Ann. des Sc, Phys. V, Ixxvi, 5, was found under calcareous debris in the mountains of Valencia. It weaves a uniform tube of a thin milk-white tissue, like that of the Dysdera erythrina. Theridion, Walck. Eight eyes disposed as follows: four in the middle forming a square, the two anterior of which are placed on a little eminence, and two on each side, also situated on a common elevation. The thorax has the figure of a reversed heart, or is nearly triangular. This subgenus is very numerous(2). Therid. malmignatte; Aranta \o-guUata, Fab.; Ross. Faun. Etrusc, 11, ix, 10, The lateral eyes separated from each other; body black, with thirteen small, round, blood-red spots on the abdomen. Its bite is considered venomous and even mortal. From Tuscany and Corsica(3). The A. mactans, Fab., a second species of Theridion inhabit- ing South America, is equally dreaded in that country. This prejudice against these animals appears to originate from their black colour, varied with sanguine spots. (1) Scytodes thoracica, Lat., Gen. Crust, et Insect. I, v, 4; Walck. Hist, des Aran., I, x, and II, Suppl. (2) See the Tab. and Hist, des Aran., Walcken., the Ann. des Sc. Nat., and Ann. des Sc. Phys. The Arane^e bipundata, redlmita, L., and the £. albo-maculata, Deg., &c., should be referred to this genus, (3) This species is the type of the genus Latrodeda, Walck., which he distin- guishes from that of Theridion by the difference in the respective length of the feet; in this, however, he appears to me to have erred. His Theridion benignum. Hist, des Aran. fasc. V, viii, whose habits he has care- fully studied, establishes its domicil between the clusters of grapes, and defends them from the attacks of various Insects. Vol. III.— Y 186 ARACHNIDES. Episinus, Walck. Eight eyes also, but they are approximated on a common eleva- tionj the thorax is narrow and almost cylindrical(l). In the remaining Inequitelae, the first pair of legs, and then the second, are the longest. Such is the Pholcus, Walck. Where the eight eyes are placed on a tubercle, and divided into three groups; one on each side consisting of three eyes, forming a triangle, and the third in the middle, somewhat anteriorly, and com- posed of two on a transverse line. Ph. ■phalangioides, Walck., Hist, des Aran., fasc. V, tab. xj Araign^e domestique a tongues pattes, Geoff. The body long, narrow, pale yellowish or livid, and pubescent; abdomen nearly cylindrical, very soft, and marked above with blackish spots; very long, slender legs; a whitish ring round the extremity of the thighs and tibia:. Common in houses, where it spins a web of a loose texture, in the angles of the walls. The female cements her eggs into a round naked mass, which she carries between her mandibles. M.Dufour has found a second species, the Pholque a queue- Ann, des Sc. Phys. V, Ixxvi, 2, — in the clefts of the rocks in Moxente, Valencia, Its abdomen terminates in a conical point, and thus forms a sort of tail, like that of the Epeira conica. Like the preceding species, it balances its body and feet. The genital organs of the male are very complex. In the third section of the sedentary rectigrade spiders, the Or- BiTELiE, or Jlraign'ees Tendeuses of others, the external fusi are almost conical, slightly salient, convergent, and form a rosette; the legs are slender, as in the preceding section, but the jaws are straight and evidently wider at their extremity. The first pair of legs, and then the second, are always the-longest. There are eight eyes thus arranged: four in the middle forming a quadrilateral, and two on each side. The Orbitelae approach the Inequitelse in the size, softness, and diversity of colour of the abdomen, and in their short term of exist- ence; but their web is a regular piece of net-work, composed of con- centric circles intercepted by straight radii diverging from the cen- tre, where they almost always remain, and in an inverted position, at the circumference. Some conceal themselves in a cell or cavity (1) Episinus truncatus, Lat. Gener. Crust, et Insect, t. IV, p. 371. Italy, and environs of Paris. PULMONARI^. 187 which they have constructed near the margin of the web, which is sometimes horizontal, and at others perpendicular. Their eggs are agglutinated, very numerous, and inclosed in a voluminous cocoon. The threads which support the web, and which can be extended one-fifth of their length, are used for the divisions of the microme- ter. This observation was communicated to us by M. Arrago. LlNYPHIA, Lat. The Linyphiae are well characterized by the disposition of their eyes: four in the middle form a trapezium, the posterior side of which is widest, and is occupied by two eyes much larger and more distant; the remaining four are grouped in pairs, one on each side, and in an oblique line. The jaws are only widened at their superior extremity. They construct on bushes a loose, thin, horizontal web, attaching to its upper surface, at different points, or irregularly, separate threads. The animal remains at its inferior portion, and in a re- versed position(l). Uloborus, Lat. The four posterior eyes placed at equal intervals on a straight line, and the two lateral ones of the first line nearer to the anterior edge of the thorax than the two comprised between them, so that this line is arcuated posteriorly. Their jaws, like those of the Epei- ras, begin to widen a little above their base, and terminate in the form of a palette or spatula. The tarsi of the three last pairs of legs terminate by one small nail. The first joint of the two posterior ones has a range of small setae. The body of these animals, as well as in the following subgenus, is elongated and nearly cylindrical. Placed in the centre of their web, they advance their four anterior legs in a straight line, and extend the two last in an opposite direction; those of the third pair project laterally. These Arachnides construct webs similar to those of other Orbi- telae, but they are looser a.nd more horizontal. They will completely envelope the body of a small coleopterous insect in less than three minutes. Their cocoon is narrow, elongated, angular at the margin, and suspended vertically to a web by one of its extremities. The other end is bifurcated or terminated by two prolonged angles one of which is shorter than the other and obtuse; there are two (1) Linyphia triangularis, Walck., Hist, des Aran., V, ix, female; Aranea resu- pina sylvestrls, De Geer; Aranea montana, L. ; Clerck., Aran. Suec, pi. Ill, Tab. I; — Aranea resiipina domesllca, Ue Geer. 188 ARACHNIDES. acute angles on each side. For these interesting observations I am indebted to my friend M. Leon Dufour. Ulohorus JVulckenaerius, Lat.(l) About five lines in length; reddish-yellowish; covered with a silky down forming two series of little fasciculi on the top of the abdomen; paler rings on the legs. From the woods in the vicinity of Bourdeaux, and in va- rious departments of the south of France. Tetragnatha, Lat. The eyes placed four by four on two nearly parallel lines, and separated by almost equal intervals; jaws long, narrow, and only widened at their superior extremity. The chelicerae are also very long, in the males especially. The web is vertical(2). Epeira, Walck. The two eyes on each side approximated by pairs, and almost con- tiguous; the remaining four forming a quadrilateral in the middle. The jaws dilate from their base, and form a rounded palette. The cuciirhitina is the only species known whose web is horizon- tal; that of the others is vertical, or sometimes oblique. Some place themselves in its centre in a reversed position, or with their head downwards; others construct a domicil close by it, either vaulted on all sides, or forming a silky tube composed of leaves drawn together by threads, or open above, and resembling a cup or the nest of a bird. The web of some exotic species is formed of such stout materials that it will arrest small Birds, and even impede the progress of a Man. Their cocoon is usually globular; that of some species, however, is a truncated oval, or very short cone. The natives of New Holland — Voyage a la recherche de la Pey- rouse, p. 239 — and those of some of the South Sea Islands, for want of other food, eat a species of Epeira, closely allied to the Jlranea esuriens, Fab. M. Walckenaer, in his Tableau des Araneides, mentions sixty-four species of Epeirse, remarkable, in general, for the diversity of their colours, form and habits. He has arranged them in various small and very natural families, the study of which we have endeavoured to simplify in the second edition of the Nouv. Diet. d'Hist. Nat., article Epeire. Certain important considerations, such as those of (1) Lat., Gen. Crust, et Insect., I, 109; see also second edition of the Nouv. Diet. d'Hist. Nat., article Ulohore. (2) Tetragnatha extensa, Walck., Hist, des Aran., V, vi; Aranea extensa, L., Fab.jDe Geer; — Jlranea virescens? Fab.; — Branca maxiUosa, Id. See Tab. des Aran, of Walckenaer. PULMONARIiE. 189 the sexual organs, had been neglected or were not sufficiently attended to; thus, for instance, the female Ep. diadema, and others, present at the part which characterizes their sex, a singular appendage, which reminds us of the apron of the Hottentot women. These species should constitute a separate division. By pursuing this ex- amination, other not less nataral divisions might be established. We will content ourselves with mentioning a few of the principal species, commencing with those that are indigenous to Europe. £p. diadema; Aranea diadema, L., Fab.; Roes., Insect. IV, XXXV — xl. Large, reddish, velvety; abdomen of the females extremely voluminous, particularly when about to lay their eggs, and of a deep brown or yellowish red; a large rounded tubercle each side of the back near its base, and a triple cross, formed of small white spots or dots; palpi and legs spotted with black. Very common in Europe in autumn. The eggs are hatched in the spring of the ensuing year. Ep. scalaris; Aranea scalaris, Fab.; Panz., Faun. IV, xxiv. Thorax reddish; top of the abdomen usually white, with a black spot in the form of a reversed triangle, oblong and dentated. weaves its web along the banks of ponds, brooks, 8cc. Ep. cicatricosa; Aranea cicatricosa, De Geer; A. impressa, Fab. The abdontien flattened, and of a greyish brown or obscure yel- lowish; a black band, festooned and edged with grey along the m.iddle of the back; eight or ten large impressed points in two lines. It constructs its web on walls or other bodies, and re- mains concealed in a nest of white silk, which it forms under some projecting object, or in some cavity in the vicinity. It only works and feeds during the night, or when the light of day is but weak. It retires under the bark of old trees or logs. Ep. sericeay Walck., op. cit., Ill, ii. Covered above with a silvery and silken down; abdomen flattened, immaculate and with festooned margins. South of Europe and Senegal. Ep. fusca, Walck., Hist, des Aran. II, i, the female. Very common in the cellars of Angers. Its cocoon is white, almost globular, fixed by a pedicle, and composed of very fine threads; it is soft to the touch, like wool. That of the Ep. fasciata, Walck., op. cit. Ill, i, the female, is about an inch long; it resembles a little balloon, of a grey colour, with longitudinal black stripes, one of whose extremities is truncated and closed by a flat and silky operculum; a fine down envelopes the eggs in its interior. This species weaves a vertical and irregular web, in the middle of which it remains, along the banks of rivulets, &c. Its thorax is covered with a soft and silvery dov/n, and its abdomen is of a beautiful yellow, inter- sected at intervals with transverse brown, or blackish-brown 190 ARACHNIDES. lines, arcuated and slightly undulated. M. Leon Dufour, Ann. des Sc. Phys. VI, pi. xcv, 5, has given a detailed description of this species, and of its habits, and was the first who ascertained the male. He has figured its sexual organ. The penis resem- bles a twisted seta. Ep. cucurhitina; Aranea cucurbitina, h.; Jl. senoculata, Fab.; Walck. Hist, des Aran., IH, iii. Smallj abdomen ovoid and lemon-coloured, marked with black points; a red spot on the anus. It weaves a small horizontal web between the stems and leaves of plants. Ep. conica; Aranea conica, De Geer and Pall.; Walck. Hist. Nat. des Aran., Ill, iii. Remarkable for its abdomen, which is gibbous anteriorly and has a conical termination; the anus is placed in the centre of an eminence. When it has extracted the juices from an insect, it suspends it to a thread. Immediately after the conica, we may place the species called by Dufour Epe'ire de Vopuntia — Ann. des Sc. Phys., V, Ixix, 3 — from the circumstance of its always weaving its loose and irregular web among the leaves of the Agave and Opuntia. It is black, with white hairs laid close to the body, having an appearance of scales. The abdomen has two pyramidal tuber- cles on each side, and terminates posteriorly in two others, which are obtuse and separated by a wide emargination. The posterior face of each tubercle is marked with a beautiful snow- white spot, resembling nacre; these spots are connected with each other, and with one or two more behind them, by white zig-zag lines. In the newly-hatched aniinal, these tubercles are not visible. The cocoons are oval, whitish, and formed of two coats, the interior of which is a kind of tow that envelopes the ova. Seven, eight, and even ten of these cocoons are frequently found arranged in file, or one after another. From Catalonia and Valencia. Some of the species foreign to Europe are very remarkable. Here we observe the abdomen is invested with an extremely firm skin, furnished with points or horny spines(l); and there the legs are provided with bundles of hairs(2). (1) The .^r. miliiaris, spinosa, cancriformis, hexacantha, tetracantha, geminata, fornicata, of Fabricius. M. Vauthier, one of our best painters of subjects of na- tural history, has described and figured, Ann. des Sc. Nat., I, p. 161, a species of this division — curvicauda — which is very remarkable for its posteriorly widened abdomen, terminated by two long arcuated spines: it inhabits Java. These spinous species might form a peculiar subgenus. (2) The .^r. pilipes, clavipes, &c., of Fabricius. His Ar. maculata forms the genus Nephisa, Leach. See the Tab. and Hist, des Aran, of Walckenaer. PULMONAKI^. 191 We now come to Spiders that are sedentary, like the preceding, but which have the faculty of moving sideways, forwards and back- wards, in a word, in all directions. They constitute our section of the Laterigrad^. The four anterior legs are always longer than the others^ sometimes the second pair surpasses the first, and at others, they are nearly equal; the animal extends them to the whole of their length on the plane of position. The chelicerae are usually small, and their hook is folded trans- versely, as in the four preceding tribes. Their eyes, always eight in number, are frequently very unequal, and form a segment of a circle or crescent; the two posterior lateral ones are placed farther back than the others, or are nearer to the lateral margin of the tho- rax. The jaws, in most of them, are inclined on the lip. The body is usually flattened, resembling a crab; the abdomen is large, round- ed, and triangular. These Arachnides remain motionless on plants, with their feet extended. They make no web, simply throwing out a few solitary threads to arrest their prey. Their cocoon is orbicular and flat- tened. They conceal it between leaves, and watch it until the young ones are hatched. MicROMMATA, Lat. — SpaTussus, Walck. Jaws straight, parallel and rounded at the end; eyes arranged four by four, on two transverse lines, the posterior of which is longest, and arcuated backwards. The second legs, and then the first, are the longest; the ligula is semicircular(l). Microm. smaragdula; Ar. smaragdula^ Fab.; Jlr. viridissima, De Geer; Clerck, Aran. Suec. pi. 6, tab. iv. A medium size; green; the sides edged with light yellow; abdomen greenish yellow, intersected on the middle of the back by a green line. It ties three or four leaves in a triangular bundle, lines the interior with a thick layer of silk, and places its cocoon in the middle; the latter is round, white, and so diaphanous, that the ova can be perceived through its parietes. The eggs are not agglutinated. M. Argelas; Dufour, Ann. des Sc. Phys., VI, p. 306, XCV, 1; Walk., Hist, des Aran., IV, ii. This animal, whose specific ap- pellation will remind the French naturalists of one of their most (1) M. Walckenaer places this genus in that series which is composed both of the Vagabund?e and the Sedentariae, such as the Mae or our Saltici, the Thomisi, Philodromi, Drassl, and Clubionx, and wliich have but two hooks to the tarsi. 192 ■ ARACHNIDES. zealous savans, one already recommended by me to their esteem as my protector from the horrors of the revolution, is one of the largest species indigenous to France; M. Dufourhas completed my description of it, and has observed its habits. The body is about seven or eight lines in length, of a cinereous flaxen colour, covered with down, and more or less spotted with black. The top of the abdomen, from its middle to the extremity, is mark- ed with a band formed of a series of small hatchet-shaped spots, of the last mentioned colour. A black longitudinal band, grey in the middle, runs along its under surface. The legs are annu- lated with black. This species was discovered by the naturalist to whom I have dedicated it, in the environs of Bourdeaux. M. Dufour has since found it in the most barren mountains of Va- lencia. It runs with great velocity, the feet being extended late- rally. Its unguiculated palettes enable it to cling to the smooth- est surface, and in every possible position. It constructs a cocoon, which in texture resembles that of the Clothoof Durand, on the under surface of stones, to which it retires for shelter in bad weather, to escape from enemies, and to lay its eggs. It is an oval tent, nearly two inches in diameter, attached to the stone in the manner of a marine Patella. It is formed of an external envelope, consisting of a yellowish taffeta, as fine as the peel of an onion, but rigid, and of an inner lining which is more supple, softer, and open at both ends. It is from these openings, which are furnished with valves, that the animal issues. The cocoon is globular, and placed underneath its dwelling, so that it can brood over it; it contains about sixty eggs. The same naturalist has described and figured another spe- cies, the M. a tarses spongieux — Ann. des Sc, Phys., V, Ixix, 6 — which he found on a tree in a garden at Barcelona. From its habits, however, and some of its characters, I presume that it belongs to the genus Philodroma of Walckenaer(l). Senelops, Duf. The Senelopes form the transition from the preceding genus to the following one. The jaws are straight or but slightly inclined. (1) For the other species, see the Tab. des Aran., Walck., and his Hist, des Aran-, fascic. IV, Sparassus roseus, X, the male; — lb., fascic. II, viii, the male. I think we should refer to this subgenus the Aranea venatoria, L., — Sloane's Hist. of Jam., CCXXV, 1, 2; Nliamdiu, 2? Pison; — and another species from India very analogous to the preceding', figured on Chinese drawings and paper-hangings. PULMONARI^. 193 without any lateral sinus, and taper to a point obliquely truncated on the inner side. The ligula is semicircular like that of the Mi- crommatae, but the eyes are arranged differently. There are six before forming a transverse line; the two others are posterior, and situated one on each side, behind each extremity of the preceding line. The legs are long; the second pair, and then the third and fourth, are longer than the first. The type of the genus, Senelops omalosoma, Dufour, Ann. des Sc. Phys. V, Ixix, 4, was found by M. Dufour in Valencia, but it is very rare there. The body is about four lines in length and very flat, of a greyish red, with cinereous spots; the feet are annulated with black. The posterior part of the abdomen seems to exhibit vestiges of annuli, forming on the sides an ap- pearance of teeth. It lives arnong rocks, and when escaping from pursuit flies with the rapidity of an arrow. It is also found in Syria — Collection of M. Labillardiere — and in Egypt. Other species inhabit Senegal, the Cape of Good Hope and the Isle of France. Philodromus, Walck.(l) The Philodromi diff'er from the two preceding subgenera in their jaws, which are inclined on the ligula, which is also higher than it is wide. The almost equal eyes always form a crescent or semi- circle. The lateral ones are never placed on tubercles or eminences. The chelicerE are elongated and cylindrical; the four or two last legs do not materially diff'er in length from the others. According to Walckenaer these animals run with great swiftness, their legs extended laterally, lie in wait for their prey, throw out solitary threads to entrap it, and conceal themselves in crevices or among leaves. In some the body is broad and flat, the abdomen short and widened posteriorly, and the four intermediate legs the longest. Such is the Philoclrome tigree; Thomise tigre, Lat.; Araneus marguritarius, Clerck, VI, iii; Schseff*., Icon;, Ixxi, 8; Frisch, Ins., Centur., II, xiv; Arcinea levipes, L. ? It is about three lines in length. Its two anterior intermediate eyes and the four lateral ones are situated on a slight elevation, and the lat- ter, according to the same naturalist, are somewhat the largest, or at least are more apparent. The thorax is very wide, flat- tened, of a reddish fawn colour, brown laterally and posteriorly, (1) In the first edition of this work, this subgenus formed our first division of the Thomisi. Vol. III.— Z 194 ARACHNIDES. and white anteriorly. The abdomen, which forms a kind of pentagon, is speckled by the red, brown and white hairs which cover it, and edged laterally with brown; there are four or six impressed points on the middle of the back. The belly is whitish, and the legs are long, slender and reddish, with brown spots. This species is very common on trees, wooden partitions, walls, &c., where it remains as if glued, with the feet extended. If touched, it runs with astonishing rapidity, or falls to the ground supported by a thread. The cocoon is of a beautiful white, and contains about a hundred eggs, which are yellow and free. The female places it in hollows of trees or clefts of posts. Sec, exposed to the north, and carefully watches it. The other Philodromi, which, according to the method of M. Walckenaer, form several small groups, have the body, and some- times the cheliceric, proportionalily longer. The abdomen is some- times pyriform or ovoid, and sometimes cylindrical. The second pair of legs and then the first or the fourth are the longest. Philodromus rombifenis, Walck. , Faun. Franc, Aran., VI, 8, the male. Its body is three lines and a half in length and reddish; the second legs and then the two last are the longest; sides of the thorax Ijrown; the abdomen ovoid, with a black or brown lozenge-shaped spot above, bordered with white. Philodromus oblongus, Walck., lb., tab. ead., fig. 9. This species, as respects the relative proportion of the legs, and the disposition of the eyes, belongs to the same division; but the abdomen is longer and almost cylindrical or forming an elon- gated cone, with three brown longitudinal streaks and points on a yellowish ground, which is also the colour of the thorax. In the middle of the latter are two brown streaks forming an elongated V. These two species inhabit the environs of Paris. Fop the other, see the Faune Fran9aise, from which we have extracted the preceding descriptions. Thomisus, Walck. The Thomisi differ from the Philodromi in their chelicerae, which are smaller in proportion and cuneiform, and in their four posterior legs, which are evidently and even suddenly shorter than the pre- ceding ones. The lateral eyes are frequently situated on eminences, while those of the Philodromi are always sessile. Here also the two posterior lateral ones are further behind than the two that are inter- mediate on the same line, while in the Thomisi these four eyes are nearly on a level. PULMONARr^. 195 The species of this genus are those more particularly designated by the name of Crab-Spiders. The males frequently differ greatly from the females in colour and are much smaller. Some of them, all exotic(l), have their eyes arranged four by four on two transverse and almost parallel lines, the posterior of which is the longest. In the others, and the greater number, the ensemble of these eyes represents a crescent, the convex side of which is forwards and out- wards. Thomisus globosus; Aranea globosa, Fab. j Aranea irregularis, Panz., Faun. Insect. Germ, fascic. LXXIV, tab. xx, female; Walck., Faun. Franc, Aran., VI, 4. Three lines long; black; abdomen globular; red or yellowish all round the back. Thomisus cristatus; Clerck, Aran. Suec, pi. 6, tab. vi, size of the preceding; body grey-reddish, sometimes brown, with scattered hairs; feet with small spines; lateral eyes largest and placed on a tubercle; a transverse yellowish stripe on the front of the thorax; two others of the same colour on the back forming a V; abdomen rounded, and a yellowish band on the middle of the back with three indentations on each side. A common species frequently observed on the ground. Thomisus citreus; Jlranea citrea, De Geer; Schaeff. Icon. In- sect., tab. xix, 13. A lemon yellow, with a large abdomen wider behind; two red or saffron coloured streaks or spots are frequently observed on the back. On flo\vers(2). A subgenus established by M. Walckenaer, under the name of Storena, but which is yet but imperfectly known, should apparently terminate this section and lead to Oxyopes, which are as nearly allied to the Crab-Spiders as to the Citigradae. The Storenae have their jaws inclined on the ligula, which is nearly of the same length, and forms an elongated triangle; the chelicerae are conical; the two ante- rior legs, and then the second, longest; the two following ones longer than the last. The eyes are arranged in three transverse lines, 2, 4, 2; the posterior, with the two intermediate ones of the second lines, form a small square, and the two anterior ones are distant(3). Other Araneae whose eyes, always eight in number, extend more (1) Thomisus Lamarck, Lat, a species allied to the ./^ranea nobilis. Fab.; — T. canceridus, Walck., ejusd.; — T. kucosia,- Jlranea regia? Fab.; — T. plagusius,- — T. pinnotheres. (2) See the Tab. des Aran., Walck.; the Faune Franc, Id., and the Ann. des Sc. Phys., for the Spanish species described by M. Dufour, see also Nouv. Diet. d'Hist. Nat. second edition, article Thomise. (3) See Tab. des Aran., Walckenaer, IX, 85, 86. 196 AIIACHNIDES, along the length of the thorax, than across its breadth, or at least almost as much in one direction as the other, and which form either a truncated curvilinear triangle or oval, or a quadrilateral, constitute a second general division, or the Vagabund^, which I have thus named to distinguish them from those of the first, or the Sedentariae. Two or four of their eyes are frequently much larger than the others; the thorax is large, and the legs robust; those of the fourth pair and then the two first, or those of the second pair, are usually the longest. They make no web, but watch for their prey and seize it, either by hunting it down, or by suddenly leaping upon it. We divide them into two sections. • The first, that of the CiTiGRAOiE, is composed of the Araignees- Loups of authors. The eyes form either a curvilinear triangle, an oval, or a quadrilateral, of which, however, the anterior side ,is much narrower than the widest part of the thorax. This part of the body is ovoid, narrowed before, and carinated along the middle of its length. The legs are usually only fit for running. The jaws are always straight, and rounded at the end. Most of the females remain on their cocoon, or carry it with them at the base of the abdomen, or suspended to the anus. Nothing but the most extreme necessity will induce them to abandon it, and when the danger is over, they always return in search of it. They also take care of their young for a certain period after they are hatched. OxYoi'ES, Lat. — Sphasus, Walck. The eyes arranged two by two, on four transverse lines, the two extreme ones the shortest; they describe a sort of oval, truncated at each end. The ligula is elongated, narrowest at base, dilated and rounded towards the end. The first pair of legs is the longest; the fourth and second are nearly equal; the third is the shortest(l). Ctexus, Walck. The eyes arranged in three transverse lines, which become gra- dually longer — 2, 4, 2 — and form a sort of curvilinear, reversed tri- angle, with a truncated apex. The ligula is square, and almost iso- metrical; the fourth pair of legs, and then the first, are the longest; the third is the shortest. (1) Sphasus heterophthalmus, Walck., Hist, des Aran. fasc. Ill, tab. viii, female; Oxyopes variegatus, Lat.; Sphasus italicus, Walck., lb., Fasc. IV, tab. viii, female; Oxyopca lineatus, Lat., Gener., Crust, et Insect. ,1, v, 5, female. See article Oxyope, in the entomolog'ical part of the Encyclop. Method., the Tab. des Aran., Walck-, and the Faune Francaise. PULMONARI^. 197 This genus was established on a large species found at Cayenne. Others have since been discovered in the same island and in Brazil, but none of them have been described. DOLOMEDES, Lat. The eyes, arranged in three transverse lines, 4, 2, 2, form a quad- rilateral, somewhat wider than long; the two posterior ones are placed on an elevation. The second pair of legs is as long as or longer than the first; those of the fourth are still longer. The ligula is square and as broad as it is high, like that of a Ctenus. In some, the two lateral eyes of the anterior line are larger than the two intermediate ones; their abdomen is an oblong oval termi- nating in a point. The females construct an infundibuliform, silky nest on the tops of trees covered with leaves, or on bushes; there they lay their eggs, and when they go abroad to hunt or are forced to abandon their retreat, they always bear off their cocoon which is attached to the base of the abdomen. Clerck says he has seen them spring upon flies which were buzzing around them(l). They inhabit the borders of streams, run over their surface with the most surprizing rapidity, and can even partly enter the water without becoming wet. The females weave a coarse irregular web, between the branches of plants, in which they place their cocoon. They watch it till the ova are hatched(2). Lycosa, Lat. The eyes of the Lycosae also form a quadrilateral, but one as long or longer than it is wide; the two posterior eyes are not placed on an elevation. The first pair of legs is evidently longer than the se- cond, but shorter than the fourth, which, in this respect, surpasses all the others. The internal extremity of the jaws is obliquely truncated. The ligula is square but longer than it is broad. Almost all the Lycosae keep on the ground, where they run with great swiftness. They inhabit holes accidentally presented to them, or which they excavate, lining their parietes with silk, and enlarging them in proportion to their growth. Some establish their domicil (1) Araneus mirabilis, Clerck, Aran. Suec. , pi. v, tab. 10; Aran, rufo-fasciata, De Geer; Ar. ohscura, Fab. See the Faune Frangaise — Dolomedes sylvaiiis — and the Ann. des Sc. Phys. — Dolomede spinimane, Dufour, V, Ixxvi, 3. (2) Dolomedes marginatus, Walck.; Araneus undatus, Clerck, V, tab. Ij De Geer, Insect. VII, xvi, fig. 13, 15; Panz., Faun., LXXI, 22; — Dolomedes Jimbriatus, Walck.; De Geer, Insect. VII, xvi, 9 — 11; — Araneus Jimbriatus, Clerck, V, tab. ii. These species compose the division of the shore Dolomedes of Walckenaer. 198 AUACIINIDES. in chinks and cavities in walls, where they form a silken tube co- vered externally with particles of earth or sand. In these retreats they change their tegument, and, as it appears, after closing the opening, pass the winter. There also the females lay their eggs. When they go abroad they carry their cocoon with them, attached to the anus by threads. On issuing from the e^^ the young ones cling to the body of the mother and remain there until they are able to provide for themselves. The Lycosae are extremely voracious, and courageously defend their dwelling. A species of this genus, the Tarentula, so called from Taren- tum, a city of Italy, in the environs of which it is common, is highly celebrated. The poisonous nature of its bite is thought to produce the most serious consequences, being frequently fol- lowed by death or Tarentism^ results which can only be avoided by the aid of music and dajicing. Well informed persons, how- ever, think it more necessary in these cases to combat the ter- rors of the imagination than to apply an antidote to the poison; medicine at all events presents other means of cure. Several curious observations on the Lycosa tarentula of the south of France have been published by M. Chabrier, Acad, de Lille, fascic. IV. This genus is very rich in species, which have not as yet, how- ever, been well characterized. Lye. tarentula; Aranea tarentula, L., Fab.; Albin, Aran., tab. xxxix; Senguerd. de Tarent. An inch long; under part of the abdomen red, crossed in the middle by a black band. The Tarentula of the south of France — Lycose narbonnaise, Walck., Faun. Franc., Aran., I, 1 — 4, is not quite so large; the under part of its abdomen is very black and edged all round with red. A similar species is found in the environs of Paris, the Lytose ouvriere, or L. fabrilis, Clerck, Aran. Suec, pi. 4, tab. ii; Walck., Faun. Frang., Aran., II, 5. Lye. saccata; Aranea saceata^ L.; Jiraneus atnentatus, Clerck, IV, tab. viii; Lister, tit. 25, f. 25. Small; blackish; carina of the thorax, obscure reddish, with a cinereous line; a little bundle of grey hairs at the superior base of the abdomen; legs of a livid red, varied with blackish spots; the cocoon flat and greenish — very common about Paris(l). (1) For the other species see the Tabl. and Hist, des Aran, of Walckenaer, and the Faune Frangaise, Aran., Id. See also the second edition of the Nouv. Diet. d'Hist. Nat., article Lycose. PULMONARI^. 199 We will terminate this section with the subgenus Myrmecia, Lat., Which seems to lead to the following one, and whose characters we have detailed in the Ann. des Sc. Nat., Ill, p. 27. The eyes form a short and broad trapeziumj there are four before in a transverse linej two others, more internal than the two last of the preceding ones, form a second transverse line^ the last two are behind the two preceding ones. The eheliceras are stout. The jaws are rounded and very hairy at the end. The ligula is nearly square; somewhat longer than broad. The legs are long, and almost filiform^ those of the fourth and first pairs are the longest of all. The thorax seems to be divided into three parts, of which the anterior is much the larg- est and square, the two others resemble knots or humps. The abdo- men is much shorter than the thorax, and is covered with a solid epidermis, from its origin to the middle. The Myr. fulva, on which I have established this genus, inha- bits Brazil; other species however appear to be found in Geor- gia, United States of America. In the second section of the Vagabundas, that of the SALTioRADiE, called by others ^firaignees phalanges,^ the eyes form a large quadrila- teral, the anterior side of which, or the line formed by the first ones, extends across the whole width of the thorax; this part of the body is almost square or semi-ovoid, plane or but slightly convex above, as wide anteriorly as in the rest of its extent, and descending sud- denly on the sides. The legs are fitted for running and leaping. The thighs of the two forelegs are remarkable for their size. The Jlraignee a- chevrons blancs of Geoffroy, a species of Sal- ticus very common in summer on walls or windows exposed to the sun, moves by jerks, stops short after a few steps and raises itself on its fore legs. If it discover a fly, or particularly a musquito, it approaches softly, and then darts upon the victim with a single bound. It leaps fearlessly and perpendicularly on a wall, being always attached to it by a thread, which lengthens as it advances. This same filament also supports it in the air, enables it to ascend to its point of departure, and allows it to be wafted by the wind from one place to another. Such, gene- rally, are the habits of the species that belong to this division. Several construct nests of silk resembling oval sacs open at both ends, betvv'een leaves, under stones, 8cc. Thither they re- tire to change their tegument and to seek shelter in bad weather. If danger menaces them there, they leave it at once and escape with speed. The females construct a sort of tent, which becomes the 200 ARACHNIDE8. cradle of their posterity, and in which the young ones, for a time, live in common Avith the mother. Certain species, resembling Ants, elevate their anterior legs and make them vibrate with great rapidity. Singular combats sometimes ensue between the males, but no fatal issue occurs. A subgenus established by M. Rafinesque, that of Tkssarops, Appears to us to approximate closely to the following one in most of its characters and habits, but to be widely removed from it, if there be no mistake, in the number of the eyes which is but four. See Ann. Gener. des Sc. Phys., VIII, p. 88. A second subgenus, which also is only known to us by description, is the Palpimanus, Duf., Described by M. Dufour in the Ann. des Sc. Phys., V, Ixix, 5, and which appears to him to be intermediate between Eresus and Salticus. The disposition of the eyes is about the same as in the first of these two subgenera. The ligula is similarly triangular and pointed, and the jaws are still dilated and rounded at the end; but according to M. Dufour, they are inclined and not straight like those of the Eresi. The terminal joint of the anterior tarsi is in- serted laterally and has no hooks. He describes one species, the Palpimane bossu. It never jumps, walks slowly, and is found under stones in Valencia, where, however, it is extremely rare. A new species has been discovered by M. Lefevre in Sicily, which appears to me to belong to this genus. In the two following subgenera there are always eight eyes; the jaws are straight. Eresus, Walck. Four eyes forming a small trapezium near the middle of the ante- rior extremity of the thorax, the other four on its sides forming a similar but much larger figure. The iigula is triangular and point- ed. The tarsi are terminated by three hooks(l). (1) Eresus cinnaberinus, Walck.-, ^ranea quatupr-guitata, Ross., Faun. Etrusc, II, 1, 8, 9; Coqueb., lllust. Icon. Insect., dec. Ill, xxvii, 12; — iranea nigra, Petag., Speclm. Insect. Calab. M. Dufour, Ann. des Sc. Phys-, has described two Spanish species; one of them the Eresus acanthophilus — VI, xcv, 3, 4 — is my Erese raye of PULMONARIiE. 201 Salticus, Lat. — Attus, Walck. Four eyes, the two intermediate of which are the largest, on the anterior part of the thorax in a transverse line, and the others near its lateral edges, two on each side; they also form a large square open behind, or a parabola. The ligula is very obtuse or truncated on the summit. There are but two hooks to the extremity of the tarsi. Several of the males have very large chelicerae. The thorax of some is very thick and sloping, (en talus) and much inclined at base. Salt. Sloanei; Araneo, sanguinolenta, L. Black; a white line formed by down on each side of the thorax; the abdomen of a cinnabar-red, with an elongated black spot on the middle of the back. South of France, on stones(l). The thorax of the others is much flattened, insensibly sloping at its base. Sometimes their body is simply oval, and furnished with hairs or thick down; the legs short and robust. Saltique chevronne; Jiranea scenica, L,; jiraignee a chevrons, Geoff.; Araignee a handes blanches, De. Geer, Insect., VII, xvii, 8, 9. About two lines and a half long; above, black; margin of the thorax, and three lines en chevron on the top of the ab- domen, white. Very common(2). Sometimes the body is narrow, elongated, almost cylindrical and shorn; the legs long and slender. Salt, formicarius; Jiranea formicaria, De Geer, Insect., VII, xviii, 1, 2; Atte fourmi, Walck., Faun. Fran9., Aran., V, 1 — 3. Reddish; fore part of the thorax" black; black band and two white spots on the abdomen(3). the Nouv. Diet. d'Hist. Nat.; the other, Eresus imperialis — V, Ixix, 2 — is closely allied to the Aranea nigra, Petagna, above quoted. These two species are figured in the Faune Frangaise, Aran., pi. IV, 3, 4, 5. See also on same plate, fig. 7, the Erese cinabre. (1) This division comprizes the following Atti of Walckenaer: bicolor, chaly- beus, niger, cupreus, muscorum, the Aranea gosslpes, De Geer. (2) h-dd, Attus tardigradus, Walck., Hist, des Aran., V, iv, female. See his Tabl. des Aran. (3) For the remaining species of this subgenus, see the Aran, of the Faune Frangaise. M. Walckenaer, author of that portion of the work, in his Tabl. des Aran., mentions a species enclosed in amber. Vol. III.— 2 A 202 ARACHNIDES. FAMILY II. PEDIPALPI. In the second family of the ArachnidesPiilmonarisB, we find very large palpi, resembling projecting arms, terminated by a forceps or a claw ; didactyle chelicerse, one finger of which is movable ; an abdomen composed of very distinct segments, without fusi at the extremity ; and the sexual organs placed at the base of the abdomen. The whole body is invested with a firm tegument ; the thorax consists of a single piece, and exhibits three or two simple eyes, approximated or grouped, near the anterior angles ; and near the middle of its anterior extremity, or posteriorly, but in the median line, two others equally simple and approximated. There are four or eight pulmonary sacs. Those which form the genus Tarantula, Fab., Have their abdomen attached to their thorax by a pedicle, or por- tion of their transverse diameter; it has no pectinated laminae at its base, nor sting at its extremity. Their stigmata, four in number, are situated near the origin of the venter, and are covered with a plate. Their chelicerae (mandibles) are simply terminated by a movable hook. Their ligula is elongated, very narrow^, and con- cealed. They have but two jaws, which are formed by the first joint of their palpi. They all have eight eyes, of which three, on each side and near the anterior angles, form a triangle; and two near the middle at the anterior margin are placed on a common tubercle or little elevation, one on each side. The palpi are spinous. The tarsi of the two anterior legs differ from the others, being formed of numerous seta- ceous or filiform joints, and without a terlTiinal nail. They are confined to the hottest portions of Asia and America. Their habits are unknown to us. They now constitute two subge- nera. Phkynus, Oliv. Palpi terminating in a claw; the body much flattened; thorax broad, and almost in the form of a crescent; abdomen ecaudate, and PULMONARIiE. 203 ihe two anterior tarsi very long and slender, resembling setaceous ■antenn3e(l). Thelyphonus, Lat. The Thelyphoni are distinguished from the preceding subgenus by their shorter, thicker palpi, terminated by a forceps or by two united fingers; by their long body with its oval thorax, and the ex- tremity of the abdomen furnished with an articulated seta forming a tail. Their anterior tarsi are short, of a uniform appearance, and composed of few articulations(2). The others have their abdomen intimately united to the thorax throughout its entire width, presenting, at its inferior base, two movable pectiniform laminae, and terminated by a knotted tail armed with a terminal sting. Their stigmata, eight in number, are exposed, and arranged four by four along the belly ; their chelicerae are terminated by two fin- gers, of which the exterior is movable. They form the genus Scorpio, Lin., Fab. Scorpions have an elongated body, suddenly terminated by a long slender tail formed of six joints, the last of which terminates in an arcuated and excessively acute point or sting, which affords issue to a venomous fluid contained in an internal reservoir, forming a long square, and usually marked in the middle by a longitudinal sulcus, presenting on each side, and near its anterior extremity, three or two simple eyes, forming a curved line, and near the middle of the back two others, also simple, tvhich are approximated. The palpi are very large, with a forceps at the extremity resembling a hand; their first joint forms a concave and rounded jaw. There is a tri- angular appendage at the origin of each of the four anterior legs, which (appendages) by their approximation have the appearance of a quadripartite lip; the two lateral divisions, hoAvever, may be con- sidered as a kind of jaws, the remaining two forming the ligula. (1) Phalangium reniforme, L.; Pall. Spic. Zool. fascic. IX, iii, 5, 6; Herbst. Monog. Phal., Ill; East Indies, the SechcUes; Herbst., lb., IV, 1, South America; Tarantula reniformis, Fab.; Pall. Spic. Zool., JX, iii, 3, 4; Herbst. lb. V, 1; ejusd. IV, 2, var.? the Antilles. (2) Phalangium caudaium, I,.; Pall. Spic. ZooL fascic. IX, iii, 1, 2, from Java. South America prod\ices another species described and figured in the Jour, de Phys. etd'Hlst. Nat, 1777; the inhabitants of Martinique call it the Vinaigricr. A third species, smaller than the preceding ones, and with fulvous feet, inhabits the peninsula beyond the Ganges. 204 ARACHNIDES. The abdomen is composed of twelve annnli, those of the tail included j the first is divided into two parts, of which the anterior bears the sexual organs, and the other the two combs. These appendages are composed of a principal, narrow, elongated and articulated piece, movable at base, and furnished along its inner .side with a suite of little hollow laminae, united to it by an articulation, that are nar- row, elongated, parallel, and similar to the teeth of a comb; their number is more or less considerable according to the species; it varies to a certain extent, and perhaps with age, in the same spe- cies. No positive experiment has yet determined the use of these appendages. The four following annul! have each a pair of pulmo- nary sacs and stigmata. Directly after the sixth, the abdomen becomes suddenly narrowed, and the remaining six, under the form of joiiKs, compose the tail. All the tarsi are alike, and consist of three joints, with two hooks at the end of the last. The four last legs have a common base, and the first joint of the hip is soldered; the two last are even partly fixed against the abdomen. The two nervous cords, proceeding from the brain, unite at in- tervals and form seven ganglions, the last of which belong to the tail. In all other Arachnides, there are never more than three. The eight stigmata open into as many white bursac, each contain- ing a great number of very slender, small lamina:, between which it is probable that the air passes. A muscular vessel extends along the back, and communicates with each bursa by two branches(l); it also distributes vessels to every part of the animal. The intestinal canal is straight and slender. The liver* is composed of four pairs of glandular clusters, which pour their humour into the intestine at four points. The male has two copulating organs arising near the combs, and the female has t»o vulvse. The latter open into a matrix consisting of several inter-communicating canals, which in the proper period are found filled with living young ones; the testes are also formed of some anastomosing vessel3(2). These Arachnides inhabit the hot countries of both hemispheres, live on the ground, conceal themselves under stones and other bo- dies, most commonly in ruins, dark and cool places, and even in houses. They i*im with considerable swiftness, curving their tail over their back. They can turn it in every direction, and use it for the purposes of attack and defence. With their forceps they seize (1) See our preceding remarks on the circulation of the Arachnides Pulmo- n arise. (2) For the anatomy of the Scorpion, see Treviranus, Marcel de Serres, and Leon Dufour, Journ. de Phys., June 1817 pulmonarIjE. 205 Onisci and various insects, Carabici, Orthoptcra, &c., on whicli they feed, pierce them with their sting by directing it forwards, and then pass their prey through their cheljcerse and jaws. They are particularly fond of the eggs of Spiders and of Insects. The wound occasioned by the sting of the europaeus is not usually dangerous. That of the Scorpion of Souvignargues, of Maupertius, of the species which I have named Roussatre (occitanus), and which is larger than the preceding one, according to the experiments of Dr Maccary courageously tried upon himself, produces serious and alarming symptoms; the older the animal the more active seems to be the poison. The remedy employed is the volatile alkali, used externally and internally. Some naturalists have asserted that the European species produce two generations in the year. That which appears to me to be the most unequivocally ascertained, occurs in August. The female in coitu is laid on her back. According to Maccary she changes her tegument previous to the produc.tion of her young. The male ex- periences a similar alteration at the same epoch. The young are produced at various intervals. The' mother car- ries them on her back for several days, during which time she never leaves her retreat, and watches over them for a month, when they are strong enough to establish themselves elsewhere and provide for their subsistence. Two years are required to qualify them for con- tinuing their species. Some have eight eyes; they form the genus Buthus of Leach. S. afer, h., Fab.; Jlfrican Scorpion^ Roes., Insect., 3, Ixv; Herbst., Monog. Scorp., 1. Five or six inches long, and of a blackish brown; the forceps large, cordate, rough and some- what hairy; anterior ^dge of the thorax deeply emarginate; thirteen teeth to each comb. From the East Indies, Ceylon. •S". roussutre; S. occitanus, Amor.; S. tunetanus, Herbst. Monog. Scorp. Ill, 3; Buthus occitanus, Leach, Zool. Miscell., cxliii. Yellowish or reddish; tail rather longer than the body, with elevated and finely crenulated lines. Upwards of twenty- eight teeth — fifty-two to sixty-five, Maccary — to each comb. From the south of Europe, Barbary, &c.— Very common in Spain. The others have but six eyes; they compose the genus Scorpio, properly so called, of the same naturalist. S. europaeus, L., Fab.; Herbst. Monog. Scorp., Ill, 1, 2. Brown, more or less dark; legs and last joint of the tail paler or yellowish; forceps cordate and angular; nine teeth to each comb. From the extreme southern and eastern departments of France. 206 ARACHNII>ES. ORDER II. TRACHEARI.E. The Arachnid cs which compose this order differ from those of the preceding one in their organs of respiration, which consist of radiated or ramified trache2e(l), that only receive air through two stigmata; in the absence of an organ of circu- lation(2); anxl in the number of their eyes, which is but from (1) The traclieze are vessels which receive the aerial fluid and distribute it to every part of the interior of the bod}-, and thus remedy the want of circulation. They are of two kinds. Those tiiat are tubular or elastic are formed of three membranes, the intermediate of which is composed of a cartilaginous elastic, fila- ment spirally contorted; the two others are cellular. The vesicular traches consist of but two membranes of the latter description. They are a kind of pneumatic pouches susceptible of being inflated and depressed. Aquatic Insects", and others that are aerial, are deprived of them. They communicate with each other by tubular tracheae. In several of the Orthoptera, where they are well developed, cartilaginous arches, formed by appendages of the inferior semi-annuli of the abdo- men, give points of attachment to the muscles.which form them. The branchiae are divided into two principal trunks which extend longitudinally throughout the body, one on each side, receiving air through lateral openings or stigmata, and then throwing off' numerous branches and twigs which distribute it. In several Insects, however, there are two other trunks more or less long, situated between the two preceding ones and communicating with them. M. Marcel de Serres distinguishes them by the term pulmonary trac^x: the others he calls arterial trachex. He also. distinguishes two sorts of stigmata: one- kind, or the ordinary stigmata, simple, and consisting of two membranous lips, furnished with trans- verse striae or fibres, and opening merely by contraction; the others, which he calls tremaercs, are formed of one or two (usually two) horny, movable pieces, opening and closing like shutters. De Geer — Dcscript., Gryllus migratorius — compares them to eye-lids. They are peculiar to certain Orthoptera, and their position shows them to be the stigmata of the niesothorax. M. Leon Dufour — Ann. des Sc. Nat., May 1826 — has given excellent figures of these various kinds of stigmata, but without employing the names of the preceding authors. It would appear from his description of the abdominal stigmata, that they have the charac- ters of the tremaeres, while tliose which he afterwards describes as diffei-ent, are the ordinary stigmata. Our own opinion is that these differences are mere simple modifications of the lips. Reaumur, Mem., I, iv, 16, has figured a stigma of this latter kind, where the lips have an internal border, which, from all appearanceSj must be corneous. By supposing them to be almost entirely of this nature, we have the tremaere of M. de Serres. Certain aquatic larvae have a peculiar respi- ratory apparatus, of which we shall speak hereafter. (2) The presence of tracheae excludes a complete circulation, that is to say. TRACHEARliE. 207 two to foiir(l). The want of sufficiently general anatomical observations, has prevented the limits of this order from being rigorously determined. Some of these Arachnides, the Pycnogonides for instance, exhibit no stigmata; their mode of respiration is unknown. The Trachearise are very naturally divided into those which are furnished with chelicerse, terminated by. two fingers, one of which- is movable, or by one that is equally so; and into those where these organs are replaced by simple laminae, or lancets, Which with the ligula constitute a sucker. *Most of these animals, however, being very small, great difficulties necessarily accompany these investigations, and it is readily perceived that such characters should only be resorted to when it is impossible to avoid it. FAMILY I. PSEUDO-SCORPIONES. In this family we find the thorax articulated, its first seg- ment much the largest, and resembling a corselet ; the abdomen is very distinct and annulated, and the palpi very large and in the form of legs or claws. There are eight legs in each sex, with two equal hooks at the extremity of the tarsi, the two anterior ones, at most, excepted, and two apparent chelicerse terminated by two fingers and two toes, formed by the first joint of the palpi. They are all terrestrial, and have an oval or oblong body. This family comprehends but two genera. the distribution of the blood to the different parts of the body, and its return from the organs of respiration to the heart. Thus, although some vessels have recently been discovered in certain Insects — Phasmse — and, although they may possibly exist in various Arachnides Trachearise, it does not exclude them from the general system. M. M. de Serres has observed that the intestinal tube of the Phalangium gives off numerous caeca or vermiform appendages, which seem to have some analogy with the hepatic vessels, and that the trachece ramify over them ad infi- nitum. (1) According to Mliller the Hydrachna umbrata has six eyes: but may this not have arisen from an optical illusion or some mistake' 208 ARACHNIDES. * Galeodes, Oliv. — Solpuga, Licht., Fab. Two very large chelicerae, with strongly dentated vertical fingers, one superior, fixed, and frequently furnished at its base with a slender, elongated, pointed appendage(l), and the other movable; large pro- jecting palpi in the form of feet or antennae, terminated by a short, vesicular joint, resembling a button without a terminal hookj the two anterior feet of an almost similar figure, equally unarmed, but smaller; the others terminated by a tarsus, the last joint of which is furnished at the end with two little pellets, and two long toes termi- nated