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the joints is at the exterior circumference angularly truncated, so that a penta- 
gonal circumference is formed, the sides of which are slightly excavated. On 
each of the sides of the angle arising from the truncation of the joints of the 
pelvis, at the exterior surface, a transverse ridge with a central perforation may 
be traced, which unites with that from the neighbouring joint, and thus offers - 
a firm articulation in each of the five excavated spaces for one of the first costal 
joints, which gain further support by resting against the column where they 
occasion the impression noticed before. : A 
I have no hesitation in saying that this animal when perfect must have borne 
considerable resemblance to Encrinites moniliformis; yet it appears: to be suf- 
ficiently distinguished from that genus by the enlarged first columnar joint, 
and the firm adhesion and growing together of the pelvis with it. It is this 
latter circumstance which at once accounts for the columnar joint never occur- 
ring without the pelvis. 
I cannot, however, omit to suggest a conjecture concerning these specimens; 
which has occurred to me as probable, with regard’ to-the anchylosing of the 
pelvis to the column. The Crinoidea in an early stage of growth, as I. have shown 
when speaking of Pentacrinus caput medusz, do not display the different joints 
of which they are composed in so distinct and well marked a manner as on 
mature age ; the calcareous matter forming their nucleus. has not yet been 
secreted in sufficient quantity, and remains so involved with the membranous 
parts, as often to render it impossible to determine the line of separation 
between one joint andthe other. Now the specimens of EUGENIA CRINITES quin- 
quangularis, occur only of a very small 8126 ነ and I have before alluded:to the 
marks of original cartilaginous consistency exhibited by one im: my possession. 
' Should then these remains be those of young animals, in which an insufficient 
calcareous secretion bas not as yet distinctly separated the plates, they might 
very possibly assume the regular character of the genus Enerinites in: a more 
advanced stage of their growth. Of course in this case it would become neces- 
sary to suppress this genus, and incorporate it in that indicated. 

