TABLE OF CONTENTS. 



XI 



CHAPTER VII. 



PACK 



PHYLUM NEMATHELMINTHES 273 

 Class I. NEMATODA . . 274 



Chaetosomatidae and 



Desmoscolecidae 291 



Class II. NEMATOMORPHA . 292 

 ,, III. ACANTHOCEPHALA 293 



CHAPTER VIII. 



PHYLUM ROTIFERA . . 299 



Order 1 . Ebizota . . 307 



,, 2. Bdelloida . . 308 



,, 3. Ploima . . 308 



., 4. Scirtopoda . . 310 



,, 5. Seisonacea . . 310 



Gastrotricha . 310 



Eclrinoderidae . 311 



CHAPTER IX. 

 THE COELOMATA . . .313 



CHAPTER X. 



PHYLUM MOLLUSC A . . .316 



Class I. LAMELLI- 



BRANCHIATA 324 



Order 1. Protobranchiata . 345 



,, 2. Filibrancblata . 345 



Sub-order 1. Anomiacea, . 345 



2. Arcacea . . 345 



3. Mytilacea . 349 



Order 3. Pseudolamelli- 



branchiata 346 



4. Eulamellibrancbiata 347 



Sub-order 1. Submytilacea . 347 



,, 2. Telliiiacea . 347 



,, 3. Veneracea . '-'AS 



,, 4. Cardiacea . 348 



5. Myacca . 348 



,, 6. PJioladttcea . 348 



,, 7. Anatinacea . 349 



Order 5. Septibranchiata . 349 



Class II. SCAPHOPODA . 349 

 , III. SOLENOGASTRES . 352 



CHAPTER X. MOLLUSCA contd. 



PAGE 



Class IV. GASTROPODA . 356 



Sub-class 1. ISOPLEURA . . 387 



,, 2. ANISOPLEUJI^ . 392 



Order 1. Streptoneura . . 392 



Sub-order 1. Aspido- 



branckiata 393 



Tribe 1. Docoglossa . . 394 



,, 2. Rhipidoglossa . . 394 



A. Zygobranchiata . 394 



B. Azygobranchiata . 395 

 Sub-order 2. Pectini- 



branchiata 395 



Tribe 1. Ptenoglossa . . 396 



2. Bachiglossa . . 396 



,, 3. Toxoglossa . . 397 



4. Taenioglossa . . 397 



A. Platypoda . . 397 



B. Heteropoda . 400 

 ,, 5. Gymnoglossa . . 402 



Order 2. Euthyneura . . 402 



Sub-order 1. Opistho- 



branchiata 403 



Tribe 1. Tectibranchiata 



(includes Pteropoda) 403 



Section 1. Bulloidea . . 405 



,, 2. Aplysioidea . 407 



,, 3. Pleurobranchioidea 408 



Tribe 2. Nudibranchiata . 409 



Tribe 1. Tri tonic-idea . 411 



,, 2. Doridioidea . 412 



,, 3. Aeolidioidea . 412 



4. Elysioidea . . 413 



Sub-order 2. Pulmonata . 414 



Tribe 1. Basommatophora . 415 



,, 2. Stylommatophora . 416 



Class V. CEPHALOPODA . 417 



Order 1. Tetrabranchiata . 443 



,, 2. Dibrancbiata . . 444 



Sub-order 1. Decapod 'n, . 444 



,, 2. Octopoda . 445 



CHAPTER XI. 



PHYLUM ANNELIDA. . . 447 



Class I. ARCHIAXNELIDA . 451 



II. CHAETOPODA. . 458 



Order 1. Polychaeta . . 458 



Phanerocephala . 475 



Sub-order 1. Nereidiformia . 475 



,, 2. Spioiiiformia . 483 



