112 



STAEFISH GALLEKY. 



out life or in the larval stages only. To this group belong the 

 Crinoidea, and the extinct Blastoidea, and Gystidea. 



Pentacrinoid stage of Antedon rosacea, 

 a, arms ; h, basals ; r, radials ; s, stalk. 



B. EcHiNOZOA, or Echinoderms without stalks at any time of 

 their existence. To this group belong the Asteroidea, OpMuroidea, 

 Echinoidea, and Holofhiirioidea. 



Ceinoidea. — This Order may be described as stalked, globular, 

 or cup-shaped Echinoderms, in' which the oral surface of the calyx 

 or disk looks upwards, and in which five jointed and generally 

 branched rays arise from the central disk. Their joints have jointed 



