xvi COMPARATIVE ANATOMY 



PAGE 



B. ONTOGENY OF THE HOLOTHURIOIDEA . .510 



C. ONTOGENY OF THE ECHINOIDEA ..... 519 



D. ONTOGENY OF THE ASTEROIDEA . . . 524 



E. ONTOGENY OF THE OPHIUROIDEA . . . 532 



F. ONTOGENY OF THE CRINOIDEA ... . 533 



XXII. PHYLOGENY . . 545 



Review of the most Important Literature .... 551 



CHAPTER IX 



ENTEROPNEUSTA , 



I. OUTER ORGANISATION ....... 562 



II. THE BODY EPITHELIUM ...... 563 



III. THE NERVOUS SYSTEM . . . . . . 564 



IV. THE SENSORY ORGANS ...... 565 



V. THE ALIMENTARY CANAL ...... 565 



VI. THE CCELOMIC SACS AND THE BODY MUSCULATURE. . . 571 

 VII. THE "HEART VESICLE" .... .578 



VIII. THE LIMITING MEMBRANES, THE PROBOSCIDAL SKELETON, AND THE 



BRANCHIAL SKELETON . . . . . .579 



IX. THE BLOOD VASCULAR SYSTEM ..... 581 



X. THE GONADS ...... .585 



XI. ONTOGENY ........ 586 



XII. PHYLOGENY ........ 591 



Literature . ... . . . . . 595 



APPENDAGE TO THE ENTEROPNEUSTA 

 I. CEPHALODISCUS ....... 596 



II. RHABDOPLEURA . .... 600 



Literature . . . . . . . .602 



INDEX . . 603 



