XVII 



ZYGOPHIURAE 



495 



Order II. Zygophiurae. 



This group includes all the common and better-known British 



FIG. 217. Aboral view of Ophioglypha (Ophiura) bullata. x 3. (From Wyville Thomson.) 



forms. They are divided into five families, all of which are 

 represented in British waters. 



Fam. 1. Ophiolepididae. 1 Arm inserted in a definite cleft 



1 Hamann, Bronn's Thier-Reich, Bd. ii. Abt. 3, Ophiuroidea, 1900, p. 910 f., 

 discriminates a family Ophiodermatidae, but gives no character by which it can 

 be distinguished from Ophiolepididae. 



