
II. Division. 
CRINOIDEA SEMIARTICULATA. 
Character of the Division. 
ቭ plate-like joints resting on the superior columnar joint, and forming 
the cup containing the viscera, articulate by transverse processés, having a mi- ۱ | 
nute central perforation. 
. 
Observation. 1 i 
Although I am acquainted with but one species strictly possessing the cha- | 
racter assigned to it (viz. that which serves me as the type for the genus | 
Poteriocrinites) yet 1 thought it advisable to constitute the division SEMIAR- 
TICULATA, to mark in a more conspicuous manner the transition from regularly 
articulating joints to plates adhering only by muscular sutures. 
