112 
STARFISH GALLERY. 
out life or in the larval stages only. To -this group belong the 
Crinoidea, and the extinct Blastoidea, and Cystidea. 
Fig. 6. 
Pentacrinoid stage of Antedon rosacea. 
a, arms ; b, basals ; r, radials ; s, stalks 
B. Echinozoa, or Echinoderms without stalks at any time of 
their existence. To this group belong the Asteroidea, Ophiuroidea, 
Mhinoidea, and Holothurioidea. 
Crinoidea. — 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 
