260 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 



Horizon and Locality. — Upper portion of the Trenton limestone ; Trenton 

 Falls, N. Y. 



I'ype in the Museum of Comparative Zoology, Cambridge. 



Rhaphanocrinns sculptus (Miller). 

 Plate X. Fig. 3. 



1882. Glyptocrinus sculptus — S. A. Millee.; Journ. Cinciu. Soc. Nat. Hist., Vol. V., p. 37, Plate I., 



Kg. 2. _ 



1883. Glyptocrinus sculptus — S- A. Miller; ibid., Vol. VI., p. 224. 



1885. Glyptocrinus sculptus — W. and Sp. ; Revision Palseocr. Part III., p. 104. 

 1889. Glyptocrinus sculptus — S. A. Miller; N. Amer. Geol. and Palseont., p. 248. 



Calyx subglobose; interradial spaces deeply depressed, especially the 

 upper portion ; section across the second costals sharply pentagonal, across 

 the distichals decagonal. Eadial ridges quite prominent, angular, stronger 

 toward the sutures than at the median portion of the plates. Somewhat 

 smaller ridges pass into the basals, forming deep triangular depressions along 

 their sides. Other ridges run from the radials and brachials to the inter- 

 radial plates, dividing the whole surface into numerous impressed triangular 

 areas. 



Infrabasals almost covered by the column. Basals of medium size, pro- 

 duced into angular processes, which point downward for a short distance 

 along the sides of the upper stem joints. Eadials and costals about as wide 

 as long. Distichals three, almost as large as the costals. The plates of the 

 third order support the arms, of which there are twenty; they are long, 

 gradually tapering, and composed of quadrangular joints which become 

 shghtly cuneate in the upper parts of the arms. The four to ^\q lower 

 joints, which are considerably the largest and sharply angular on the out- 

 side, take part in the calyx \ the succeeding ones are free, much shorter, and 

 rounded. Pinnules long and slender. Interradial spaces deeply depressed 

 between the distichals ; the plates arranged : 1, 2, 3, 3, etc. The anal side, 

 which is a little wider, has a few additional plates, but no anal ridge. Inter- 

 distichals : 1, 2, 1. Structure of ventral disk unknown. Column round, 

 slightly tapering downwards, the nodal joints, near the calyx, wider and 

 considerably longer than the intervening ones, but at two inches below the 

 latter reach almost the same size. 



Horizon and Locality. — Upper part of the Hudson River group \ Warren 

 Co., Ohio. 



Types in the collection of I. H. Harris, Esq., at Waynesville, 0. 



