FOSSILS OF THE KEOKUK GROUP. 505 



broad low dish, many times wider than high, with the mar- 

 gins sinuous above for the reception of the next range of 

 pieces. Succeeding range of plates presenting the usual 

 irregular form of the genus, two of them being much larger 

 than the others, very wide at the top, and supporting nearly 

 or quite all of the arms; between these on one side there 

 is a much smaller triangular piece on the same range, and 

 extending up as high as the others, but so narrow at the 

 top that it could not have supported more than one or two, 

 if any, of the small arms. On the opposite side there are 

 two other small intercalated pieces, the smaller of which 

 is triangular and scarcely extends up to the top of the cup, 

 while the other is oblong, extends to the top of the cup, 

 and supports either another somewhat smaller (anal?) piece 

 above, or the base of an arm much larger than the others. 

 Arms about 44, in contact at their bases, and all slender, 

 and composed of joints two or three times as long as wide. 

 Surface smooth. Column comparatively very large (cir- 

 cular 0, with a large round central canal, and composed 

 near the base of rather thin pieces of uniform size. 



Hight of body, 0.18 inch; breadth at top, 0.24 inch; 

 breadth of column at the base of the body, 0.13 inch. 



This species will be at oiice distinguished from C. Tennesseece, of 

 Troost. by its much smaller size, and smooth instead of coarsely 

 granular plates. It is much more nearly allied to our C. Wachsmuthi, 

 from the Burlington group, but its body is less expanded at the top, 

 and it also differs in having a comparatively large anal ? piece, or larger 

 arm, between the others on one side. Xamed in honor of Prof. FBAXK 

 H. BRADLEY, of Hanover College, late of the Illinois Geological Sur- 

 vey, who discovered the only specimen known. 



Locality and position- Crawfordsville, Indiana ; Keokuk division of 

 Lower Carboniferous series. 



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