40 



is located on an ovate elevation. The vault of this species is alto- 

 gether different from that in Gilbertsocrinus spinic/erns so that no 

 comparison with it is necessary. 



Found iu the Hamilton group, at Charleston, Indiana, and now 

 in the collection of Wm. F. E. Gurley. 



Family TAXOCRINID.E. 



ONYCHOCKINUS TULiSKIENSIS, n. sp. 



Plate IV, Firj. 1, view apposite the azycjous side, with four und 



one-third inches of the colli mn : Fig. 2, azygons side of the 



same sj^ecimen untliout ihe column, the specimen 



is compressed antero-posieriorly which 



makes the head appear too wide. 



Species large and robust. Calyx very low, saucer-shaped. Plates 

 finely granular. Sutures distinct. Column very large and within 

 sixth-tenths of an inch of the calyx, tapering and composed of very 

 thin plates, but below that composed of thick plates, some thicker 

 than others and projecting beyond them, but not regularly alter- 

 nating at all times, though becoming more regular iu this respect 

 an inch or two below the calyx. It is somewhat elliptical and 

 pierced by a long-rayed stellate canal. 



Basals covered by the column. Subradials very short and supe- 

 rior angles obtuse. Primary radials four in each ray and diffeiiug 

 but little in size, the first and fourth are the longer and subequal. 

 Each one is wider than high and the third one is nearly twice as 

 wide as high. The sutures are transverse. The fourth plate iu 

 each ray is axillary and supports the second series of radials, the 

 plates of which are very long, (juite as long as those in the first 

 series, excepting the first and fouith. In one of the rays of our 

 specimen, seven of the plates are preserved as shown in figure 1, 

 and a small armlet is thrown off from the fifth plate. 



One iuterradial is preserved in three of the area?, and there 

 may not have been any more, except in the azygous area, where 

 th(u-e were evidently several small {jlales, in addition to the one 

 preserved. 



There is no described species for which this one might be mis- 

 taken and hence there is no necessity for drawing comparisons. 



Found by Prof. A. (i. Wetherby in the Kaskaskia Group, in 

 Pulaski county, Kentucky, and now in the collection of Wm. F. 

 E. Gurley. 



