15 



the second range, and above these there is intercalated a sin 

 gle plate which is below the union of the first quaternary 

 plates. 



Vault moderately convex and covered with polygonal convex 

 and tumid plates. The proboscis is subcentral, but it is broken 

 away from our specimen. 



This is the first Batocrinus ever described, having twenty- 

 seven ambulacral openings to the vault, and, consequently, the 

 arm formula alone distinquishes it from all other species. It 

 is peculiar also in its form and azygous plates. 



Found by F. A. Sampson in the Burlington Group, at Sedalia, 

 Missouri, and now in his collection. 



BATOCRINUS NITEUS, 11. Sp. 



Plate /, Fig. 30, basal view; Fig. 31, azygous side; Fig. 32, 



opposite view. 



Species medium size, biturbinate. Calyx moderately trun- 

 cated, obconoidal, in the lower part, and rapidly spreading 

 near the arms, which are directed horizontally, and the radial 

 series project beyond the interradial areas so as to give it a 

 stellate outline. No radial ridges. Plates without ornamenta- 

 tion. Sutures distinct. 



Basal plates form a low cup, having a height about equal to 

 half the diameter of the base, w r hich is truncated only the size 

 of the column. Depression for the attachment of the column 

 moderately concave. Columnar canal small. First primary 

 radials large, wider than long, three hexagonal, two heptag- 

 onal. Second primary radials quadrangular, and about twice 

 as wide as long Third primary radials a little larger than 

 the second, about twice as wide as long, pentagonal, axillary and, 

 in the two rays adjoining the azygous area, bear upon the proximal 

 sides two secondary radials, the last of which are axillary and sup- 

 port upon each superior sloping side two tertiary radials, and bear 

 upon each distal side three secondary radials, which gives to 

 each of these rays three arms. In each lateral ray the third 

 primary radials support on each upper sloping side two sec- 

 ondary radials, the last being axillary and supporting on each 

 superior side two tertiary radials, which gives to each of these 

 rays four arms. The ray opposite the azygous area bears 



