18 



men illustrated; but in other specimens in some of the areas, 

 there are only two plates, one following the other. There are 

 eight azygous interradials in the specimen illustrated, the first 

 one heptagonal, in line with the first primary radials and of 

 about the same size. It is followed by three plates, the mid- 

 dle one being the smaller, and these are followed by four 

 smaller plates that are cut off from the vault by the union of 

 the tertiary radials. In some of the other specimens, there 

 are only three plates in the third range and, hence, only seven 

 azygous plates. The vault is conoidal, covered with convex 

 pjlates and bears an almost central proboscis. 



This species is distinguished by its trim, neat form, beveled 

 plates and twenty ambulacral openings to the vault. This is 

 one of the forms that might be referred to Eretmocrinus, if 

 that were a valid genus. 



Found in the Keokuk Group, at Boonville, Mo., and now in 

 the collection of S. A. Miller. 



BATOCRINUS PECULIARIS, n. Sp. 



Plate I, Fig. 14, azygous side view; Fig. 15, basal view; Fig. 

 16, summit view of ihe same specimen. 



Species below medium size. Calyx somewhat obconoidal, but 

 spreading upward canopy-like, and directing the ambulacral 

 openings horizontally. Truncated nearly three times the diam- 

 eter of the column; plates moderately convex; sutures plain; 

 surface granular. Column small; canal cinque foil. 



Basals form an hexagonal disc nearly three times the di- 

 ameter of the column, concave centrally below for the attach- 

 ment of the column, and having a height equal to about half 

 the diameter of the column. First primary radials wider than 

 high. Second primary radials quadrangular, three times as 

 wide as high. Third primary radials pentagonal, larger than 

 the second, nearly three times as wide as high, axillary and 

 support on the upper sloping sides the secondary radials. On 

 the distal side of each ray adjoining the azygous area there 

 are three secondary radials, and on the proximal side two sec- 

 ondary radials, the last of which is axillary and bears upon 

 each upper slopping side two tertiary radials, which gives to 

 each of these rays three arms. One of the lateral rays is coi> 



