x TABLE OF CONTENTS 



PAGE 



Class III. Scaphopoda 325 



Class IV. Gasteropoda 325 



Order I. Prosobranchiata 333 



Order II. Opisthobranchiata 334 



Order III. Pulmonata 335 



Class V. Cephalopoda - 336 



Order I. Tetrabranchia 346 



Order II. Dibranchia 347 



SUMMARY 347 



Phylum IX. ARTHROPODA 349 



Class I. Crustacea 359 



Sub Class I. Trilobitas 363 



Sub Class II. Phyllopoda 365 



Order I. Branchiopoda 366 



Order II. Cladocera 366 



Sub Class III. Copepoda 366 



Order I. Eucopepoda 369 



Order II. Siphonostomata 369 



Sub Class IV. Ostracoda 371 



Sub Class V. Cirripedia 371 



Sub Class VI. Malacostraca 374 



Legion I. Leptostraca 375 



Legion II. Thoracostraca 375 



Order I. Schizopoda 375 



Order II. Stomatopoda 376 



Order III. Decapoda 377 



Order IV. Cumacea 382 



Order V. Syncarida 382 



Legion III. Arthrocostraca 383 



Order I. Amphipoda 383 



Order II. Isopoda 385 



Class II. Acerata 387 



Sub Class I. Gigantostraca 388 



Order I. Xiphosura 388 



Order II. Eurypterida 389 



Sub Class II. Arachnida 389 



Legion I. Arthrogastrida 391 



Order I. Scorpionida 391 



Order II. Phrynoidea 392 



Order III. Microthelyphonida 393 



Order IV. Solpugida 393 



Order V. Pseudoscorpii 394 



Order VI. Phalangida 394 



Legion II. Sphuaerogastrida * 395 



Order I. Araneina 395 



Order II. Acarina 396 



Order III. Linguatulida 397 



Tardigrada 398 



Pycnogonida 399 



Class III. Malacopoda 309 



Class IV. Insecta JQO 



Sub Class I. Chilopoda 402 



