18 



The vault is oonoidal and about as large as the calyx. It is 

 covered with smooth, polygonal plates and boai-s a long, small 

 contral proboscis. 



This species is distinguished by the smooth plates of both 

 the calyx and vault, by the sixteen arabulacral openings, with 

 a formula of 3-f-4 + 2+4+3, and thirty-two arms. It is further 

 distinguished by the six plates in the azygous area. Only three 

 species have been, heretofore, described froni the Keokuk 

 (ri-oup with thirty-two arms, and none of them resemble this 

 one. There have been fifteen species described from the Keokuk 

 (Ji-oup with sixteen arms and i)ossibly one or two of these have 

 thii-ty two arms, but tli(\y ai'c onianiented s])(>cies l^earing radial 

 i-i(.lgcs and lia\c little j-e.semblaiici' to this one. It is unneces- 

 sai-y to make any comparison with any other specit^s. 



l'\)und in the KeoK-ulc (iroup, at Boonville, Mis.souri, .-uid tlif 

 s])ecim('n having the arms with other specimens iivv in the 

 collection of Wm. l'\ K. Curley, and the one showing the vault 

 and others are in the collection of S. A. Miller. It preserves 

 part of the arms opi)osite to the side illustrated. 



Remarks. — The arms flatten as they apijroach the superior 

 ends and when they curve in or infold toward the vault they 

 become longitvidinally concave in all the si)ecimens. This is 

 another illustration of the r\i1ility of uiidertaK'ing to establish 

 genera on the character of the arms, for if you can do so, this 

 would belong to Ereimocrinus or to a new genus, according to 

 the taste of the author. 



BATOCBINUS FABERI, n. sp. 



Flate II, Fig. .?. azygous side: Fig. 4, op;'o>'i(e vii-n: 



Body rather below medium size and somewhat biturbinate or 

 wheel sha]ied, though the calyx is decidedly larger than the 

 vault. Calyx truncated below and slowly expanding to the 

 third radials and then abrujitly spreading to the free arms. 

 Arm opening.«< directed horizontally. Twice as wide as high. 

 No radial ridges. Plates slightly convex in the superior part 

 and tumid below. Surface granular. 



Basals short and form a low subhexagonal disc, with slight re- 

 entering angles. The disc is about one- fourth wider than the 

 diameter of the column mid bears a shallow concave depres- 



