20 



BATOCRINUS IMPARILIS, n. Sp. 



Plate I, Fig. 17, azygous view; Fig. 18, opposite azygous side 



We have several specimens of this species varying from half 

 the size of the one illustrated to about one-fourth larger. None 

 of them show any of the arms, and the one illustrated is best 

 preserved. 



Calyx urn- shaped; about one-fourth wider than high, though 

 sometimes nearly as high as wide. Plates tumid; no radial 

 ridges; sutures distinct; column small; surface granular. 



Basals form a very low hexagonal cup about three times as 

 wide as the diameter of the column. The columnar facet is 

 round, deep and preserves the serrated lines for the attachment 

 of the column. The convexity of the plates extends below the 

 point of attachment of the column. The first primary radials 

 are much larger than any other plates in the body and have 

 a height nearly equaling the width. Second primary radials 

 quadrangular, about twice as wide as high. Third primary 

 radials very little larger than the second, pentagonal, axillary, 

 and support on each upper sloping side of three rays two 

 secondary radials, which gives to each of these rays two arms. 

 Each third primary radial adjoining the azygous area bears 

 upon the distal upper side two secondary radials, the last 

 one bearing a single arm, and upon the proximal side two 

 secondary radials the last of which is axillary and bears upon 

 each upper sloping side a single tertiary radial which gives 

 to each of these rays three arms. There are, therefore, twelve 

 arm openings to the vault in this species. 



There are three regular interradials in each area, one large, 

 the other two smaller, somewhat elongated, and unite with the 

 plates of the vault. The azygous area is large. The first 

 plate is in line with the first primary radials and of about the 

 same size. It is followed by three rather large plates, in the 

 second range, and these, by three small plates, in the third 

 range, that unite with three plates that separate the arms and 

 unite with the plates of the vault. The vault is convex and 

 covered with convex polygonal plates. The proboscis is small 

 and subcentral, but it is broken off close to the vault in all 

 our specimens. 



