5] 



each upper side, three secondary radials, which gives to it two 

 arms. There are, therefore, seventeen arms in this species. The 

 arm formula is 5+3+2+3+4. 



The interradial areas are unequal, but all are separated from 

 the plates of the vault. In each of two areas there are two plates, 

 one following the other. In another area there are three plates, 

 one followed by two in the second range. In the other area there 

 are four plates, one followed by two in the second range, and one 

 iu the third range. There are eight plates in the azvgous area. 

 The first one is in line with the first primary radials and some- 

 what smaller than either of them. It is followed by three plates, 

 in the second range, three in the third range, and one in the 

 fourth range, which is cut off from the vault by the union of tbe 

 tertiary radials above it. 



The vault is highly convex and covered with plane, smooth, 

 polygonal plates. It bears a subcentral proboscis. No ovarian 

 pores discovered. 



This species bears little resemblance to any other seventeen 

 armed species, and, of course, need not be compared with any 

 other; though its general appearance may be said to resemble B. 

 rotundus, from which it is very widely separated in the essential 

 elements of structure. 



Found in the Burlington Group, at Burlington, Iowa, and now 

 in the collection of A. Albers. 



BATOCRINUS SUBSCTTULUS, n. sp. 



Plate III, Fig. 9, view opposite the azygous area; Fig. 10, basal 

 view; Fig. 11, summit. 



Species medium size, biturbinate, or Fomewhat wheel- shaped. 

 Calyx two and a half times as wide as high, most rapidly spread- 

 ing toward the arms, which are directed horizontally, and leaving 

 the sides concave or a broad constriction from the basals to the 

 arms. Surface of the plates plain and smooth. 



Basals form a low expanding cup twice as wide as the diam- 

 eter of the column and having an hemispherical depression for the 

 attachment of the column. First primary radials between two and 

 three times as wide as long, three hexagonal, two heptagonal. 

 Second primary radials quadrangular, three or four times as wide 

 as long. Third primary radials only a little larger than the sec- 

 ond, three hexagonal, one heptagonal and one pentagonal, axillary, 

 and in each of four of the rays support, on each superior sloping 



