BRANCH CCELENTERATA : THE POLYPS, ETC. 107 



sea-fans, delicate, branching, tree-like forms found all 

 over the world. 



J Ctenophora. The members of this class are mostly 

 small, peculiar jellyfishes which do not form colonies, and 

 are extremely delicate, being usually perfectly trans- 

 parent. They swim by means of cilia. They never 

 appear in a polyp condition, but are always medusoid in 

 shape. 



