6 



fore, fourteen arms, in this species, and fourteen ambulacra! open- 

 ings to the vault. 



The regular interradial areas are not exactly alike. In two of 

 them there is a single plate and in the other Iwo areas a small 

 plate follows the first one. In the azygous area, the first plate is 

 in line with the first radials and it is followed by three plates of 

 nearly equal size, giving to this area a subqiiadrate outline. 



The vault is enormously developed, most tumid opposite the 

 azygous area and covered with large, polygonal, unequal, and re- 

 markably heavy spinous plates. The proboscis is large, subcentral 

 and slightly curved back from the azygous side. There are two 

 pores that penetrate the vault between each of the arms or twenty- 

 eight of these passages in the species. 



This species is distinguished by the development of each radial 

 series at the periphery of the calyx which gives to the calyx its 

 subpentag )nal outline; by the great development of the vault; by 

 the robust spinous plates and fourteen arms. It has some resem- 

 blance to Eretmocrinus prtvgravis, which is a twelve armed spe- 

 cies and has more plates in the azygous and regular areas. It 

 may be said to be constructed upon a similar plan, though not to 

 be mistaken for that sfjecies. We think that Eretmocrinus priv- 

 cjravis should be referred to Balocrinns, and possibly the genus 

 Eretmocrinus abandoned, at least, the large proboscis, no matter 

 how much it may bd curved, will not alone distinguish Eretmocri- 

 nus. 



Found by Prof. A. G. Wetherby, in the Keokuk Group, on 

 Little Barren Kiver, Kentucky, and now in the collection of Wm. 

 E. E. Gurley. 



BATOCRINUS CUKI08US, n. sp. 



Plaie I, Fig. 4, azygous side; Fig. 5, opposite view; Fig. 0, hasal 



view. 



Species large, vault exceeding the calyx in dimension. Calyx 

 more than twice as wide as high, truncated below, regularly expand- 

 ing to the first tertiary radials, and then spreading nearly horizon- 

 tally to the free arms. Ambulacral openings directed horizontally. 

 Each primary, secondary, tertiary and quaternary radial series 

 consists of a sharp ridge that slopes laterally to the sutures, the 

 sharp angularity increases from the first primary to the last qua- 

 ternary plate, each plate also bears a sharp central node or tuber- 

 cle. All other plates of the calyx are tumid and each bears a 

 central node. Surface granular. Column large and contains a 

 large canal. 



