12 



and the largest plate in the body. It is followed by three 

 plates in the second range, three smaller ones in the third 

 range, two in the fourth range and one narrow, elongated 

 plate in the fifth range, that separates the quaternary radials 

 and unites with two plates that belong to the vault. 



Vault convex, moderately depressed toward the interradial 

 areas and strongly depressed toward the azygous area, and 

 covered with numerous convex, polygonal plates. It bears a 

 rather large, subcentral proboscis. 



This is the only species of Batocrinus having twenty-four 

 arms, from the Burlington Group, except B. quasillus, and it 

 is so different, in general form and in the structure of the azy- 

 gous and interradial areas from that species, that no compari- 

 son is necessary to distinguish it. It is quite unnecessary to 

 compare it with any other species. 



Found by R. A. Blair, in the Burlington Group, at Sedalia, 

 Missouri, and now in the collection of S. A. Miller. 



BATOCRINUS ASPERATUS, n. Sp. 



Plate I, Fig. 13, azygous view; Fig. 14, side view. 



Body about medium size, laterniform or urn-shaped. Calyx 

 broadly truncated below and slowly expanding above; about 

 one- third wider than high. Arm openings directed upward at 

 an angle of about thirty degrees. No radial ridges. Plates 

 tumid and spiniform. Surface smooth or finely granular. 



Basal s short, forming an hexagonal disc, with re-entering 

 angles, deeply notched at the sutures and projecting cuneiform 

 edges below the end of the column and having a shallow con- 

 cave depression for the attachment of the column. The basal 

 disc is more than one-half wider than the diameter of the 

 column. First radials a little wider than high, three hexag- 

 onal, two heptagonal, and each one bears a transverse cuneiform 

 spine. Second radials quadrangular, two or three times as wide 

 as long. Third radials larger than the second, pentagonal, ax- 

 illary, and support on each upper sloping side two secondary 

 radials, the last one being axillary and supportLi. r ; on each 

 upper sloping side a single tertiary radial, except o:i the prox- 

 imal sides of the rays adjoining the azygous area, whore there 

 are two tertiary radials. There are, therefore, four arms to 

 each ray, or twenty arms in this species. There is only one 

 regular interradial in each area and it is spiniform. In the 

 azygous area there are four spiniform plates. The first one is 



