TIJi: STAllFISU 



Fig. 250. — Caudina, the 

 tailed HolotFiuriau. a, 

 mouth ; h, anus. After 

 Selenka. 





Fig. 251. — Sjjnnptainherens. 

 a, tentacles ; h, longitudinal 

 muscles ; c, alimentary tract. 

 After Quatrefages. 



Fio. 252. — A sea lily, Metacrlnus inter- 

 ruptus. After P. H. Carpenter. 



