296 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 



upward. Anal interradius considerably wider, and flattened instead of being 

 grooved as in the case of the other four ; the first plate is the largest, and is 

 followed by three pieces in the second row, and these by three or four pieces 

 in the succeeding rows. Interdistichals four, rather large and longitudinally 

 arranged ; the upper one resting between the two proximal palmars. Nothing 

 is known of the ventral disk, nor of the anus. Column large, round, com- 

 posed near the calyx of moderately long joints alternating with shorter ones; 

 suture lines distinctly waving. 



Horizon and Locality, — Pentamerus limestone ; Litchfield, Herkimer 

 Co., N. Y., and apparently also found in the Niagara group of Western 

 Tennessee. 



Ti/pes in the American Museum of Natural History, New York. 



Melocrinus pachydactylus (Conrad). 

 Plate XXIII. Figs. 4 ctnd 5, and Plate XXIV. Figs. Jfa^ h. 



1841. Astrocrinites 'pacJiydadyltis — Conead; Ann. Rep. Palaeont. N. Y., p. 34. Also Mather 1843; 



Geol. Rep. N. Y., p. 246. 

 1859. Mariacrinus pachydactylus — Hall ; Paleeont. N. Y. Vol. III., p. 107, Plate 3, Pigs. 1-4. 

 1881. Melocrinus pachydactylus — W. and Sp. ; Revision Palseocr., Part II., p. 123. 



Syn. dctinocrinus polydactylus Bonny (not S. A. Miller) ; Schenectady Reflector of 1835. 



Syn. Mariacrinus paucidactylus Hall ; Palseont. N. Y., Yol. III., p. 109, Plate 3, Pig. 5. 



Syn. Melocrinus paucidactylus — W. and Sp. ; Revision Palseocr., Part II., p. 122. 



Smaller than the preceding species; dorsal cup shorter and with convex 

 sides ; interradial spaces not grooved, although slightly impressed in the 

 upper portions \ the radiating ridges upon the surface much more conspicu- 

 ous, and ending m a node at the centre of the plates ; the arms given off at 

 greater intervals, and the pinnules less closely packed together than in that 

 species. 



Basals formed into a short spreading cup, of which the lower margin 

 is slightly projecting. Kadials and costals of nearly equal size, as wide 

 as long ; both covered by a broad, flattened ridge, which bifurcates on the 

 second costal and follows the distichals. Narrower ridges pass out to the 

 interbrachials. Distichals 3 X 10, smaller than the costals. The axillaries 

 support upon the inner sides of the ray from seven to eight palmars, which 

 are laterally connected ; at their outer sides the proximal arms, of wdiicli 

 the ^-^^ lower plates are considerably the longest, and form part of the calyx. 

 The two lower palmars of each side are longer than the upper ones, and 

 those of the one division are separated from those of the opposite side by a 



