ECH INODE li MATA. 
Medusae (Fig. 107), and Pentacrimis Europmus (Fig. 108). These 
curious zoophytes resemble a flower borne upon a stem, which ter- 
minates in an organ called the calyx, hut which is, properly speaking, 
Oie head of the animal. Arms, more or less branching, spring from 
Fig. 108. Pentacrinus Europteus (Thompson). 
calyx, their ramifications, so formed, consisting of many pieces 
arti <mlated to each other. The calyx is supported by a stem, varying 
m height, formed 0 f pieces secreted by the living tissues which surround 
The articulations of this stem are usually very numerous, 
t 2 
