472 
RADIATA. 
RADIATA. 
Class I. ECH I NODERM AT A. — Skin coriaceous or crusta- 
ceous ; intestinal canal distinct, and contained in an 
abdomen; numerous apparent vessels connected with 
circulation aud reproduction. Marine. 
II. ACALEPHA. — Skin soft, frequently gelatinous ; 
stomach and intestines never floating in a particular 
cavity ; traces of circulating vessels obscure. Ma- 
rine. 
III. ZOOPHYTA. — Mouth surrounded by a circle of 
tentacula ; body generally compound, and assuming 
plant- like forms. 
IV. INFUSORIA. — Apparently destitute of a visible 
mouth, stomach, or internal vessels. 
