CO MP A RA TI VE A NA TOM Y 



B. Ontogeny of the Holothurioidea 



C. Ontogeny of the Echinoidea . 



D. Ontogeny of the Asteroidea . 



E. Ontogeny of the Ophiuroidea . 



F. Ontogeny of the Crinoidea 



XXII. Phylogeny .... 



Review of the most hnpon-tant LitcratiLre 



510 

 519 

 524 

 532 

 533 



545 

 551 



CHAPTER IX 



ENTEROPNEUSTA 



I. Outer Organisation . 

 II. The Body Epithelium 



III. The Nervous System 



IV, The Sensory Organs 



V, The Alimentary Canal 



VI. The Ccelomic Sacs and the Body Musculature 



VII. The "Heart Vesicle" 



VIII. The Limiting Membranes, the Proboscidal Skeleton, and the 

 Branchial Skeleton 



IX. The Blood Vascular System 



X. The Gonads . . 



XI. Ontogeny 



XII. Phylogeny 

 Literature 



562 

 563 

 564 

 565 

 565 

 571 

 578 



579 

 581 



585 



591 

 595 



Appendage to the Enteropneusta 



I. Cephalodisous 



II. Rhabdopleura 

 Literature 



596 



600 

 602 



Index 



603 



