Echinodermata. 347 



organs. The echinoderms are a very distinct group, 

 standing apart from all other branches of the animal 

 kingdom. 



CLASSES OF ECHINODERMATA. 



Class I. Asteroidea Starfishes. 



Class II. Ophiuroidea Sand Stars and Brittle Stars. 



Class III. Echinoidea Sea Urchins and Cake Urchins. 



Class IV. Holothuroidea Sea Cucumbers, or Sea Slugs. 



Class V. Crinoidea Sea Lilies and Feather Stars. 



