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Cincinnati Society of Natural History. 



and above about 6 small plates; only 2 plates observed in 

 intersecondary radial spaces; azygous space filled by a range 

 of elevated plates resting on one of the basal plates; arms 

 moderately long, composed of very short plates, with long, 

 strong pinnules ; column small, round. (Jour. Cin. Soc. Nat. 

 Hist., Vol. I, p. 28, as Glyptocrinus; Miller, Ibid., Vol. VI, 

 1883, p. 229, as Gaurocrinus.) 

 Locality. — Cincinnati, O. 



2. — P. parvus Hall, 1872. 



Body small, narrow, turbinate to the bases of the free arms ; 

 basals about equal in height and width ; radials sub-equal, 

 the first ones a little the largest; rays divided on the third 

 radial, and again on the second supraradial, above which the 

 pieces are smaller and soon become free, forming the arms ; 

 interradial areas, containing about 6 or more plates, varying 

 from pentagonal to heptagonal ; inter-supraradials 1, 2, or 

 more ; arms long and slender, with tentacles on the sides of 

 alternating plates, long and comparatively strong; siirface of 

 plates smooth, and the center of those composing the rays 

 strongly elevated, forming a strong ridge along the ray to the 

 arms. (24th Rept. N. Y. State Mus. Nat. Hist., p. 207, as 

 Glyptocrinus \ 2d edition of 20th Repts. of Ibid., 1891.) 



Locality. — Cincinnati, O. 



Remarks. — Hall says of this that it " may possibly prove to 

 be the young" of Glyptocrinus decadactylus. 



Genus 5.— GLYPTOCRINUS Hall, 1847. 



Calyx obconical to subglobose ; surface ornamented with 

 radiating striae in the form of elevated ridges, dividing into 

 numerous triangular impressed areas ; under-basals absent; 

 basals 5, uniform in size, small, scarcely extending to the sides 

 of the body, slightly concave for the attachment of the 

 column ; primary radials 3 X 5> the lower series somewhat 

 larger, nearly similar in form, the second hexagonal; the 

 third pentagonal in outline, and supporting the secondary 

 radials ; secondary radials varying in number from 2 to 8 or 



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