xii COMPARATIVE ANATOMY 



PAGE 



B. SPECIAL .... . .201 



1. AMPHINEURA . . . . . . .201 



2. GASTROPODA . . . . . . .201 



3. SCAPHOPODA ....... 206 



4. LAMELLIBRANCHIA ...... 206 



5. CEPHALOPODA ....... 208 



XVIII. THE BODY CAVITY . 211 



XIX. THE NEPHRIDIA . . 215 



A. AMPHINEURA . . . . . . .216 



B. GASTROPODA ...... 217 



C. SCAPHOPODA ....... 221 



D. LAMELLIBRANCHIA . ..... 221 



E. CEPHALOPODA ....... 222 



XX. GENITAL ORGANS ... ... 225 



A. GENERAL ........ 225 



B. SPECIAL ........ 227 



XXI. PARASITIC GASTROPODA ...... 244 



XXII. ATTACHED GASTROPODA .... . 248 



XXIII. ONTOGENY .... ... 248 



A. AMPHINEURA ....... 248 



B. GASTROPODA ....... 252 



XXIV. PHYLOGENY .... . 268 

 Reviciv of the most Important Literature .... 269 

 APPENDAGE, RHODOPE VERANII . 281 



CHAPTER VIII 



ECHINODERMATA 



Systematic Review ..... . . 285 



CLASS I. HOLOTHURIOIDEA ..... 285 



II. ECHINOIDEA ....... 288 



III. ASTEROIDEA ....... 295 



IV. OPHIUROIDEA .... . . 299 



V. PELMATOZOA . .... 302 



1. CRINOIDEA . ..... 302 



2. CYSTIDEA. ....... 313 



3. BLASTOIDEA . . . . . . .314 



I. GENERAL MORPHOLOGY OF THE ECHINODERM BODY . . 315 



II. MORPHOLOGY OF THE SKELETAL SYSTEM 317 



