15 



nan a first primary radial and in line with thorn. It is followed 

 by three plates in the second range, two quite small plates in 

 the third range and three plates in the fourth range that 

 separate the arms and unite with four plates belonging to the 

 vault. 



The vault is only moderately convex and terminates in a 

 large subcentral proboscis, that is broken away from our 

 specimen. The vault is covered with numerous, slightly 

 convex, polygonal plates. 



This is the first ten armed species of Batocrinus described 

 from the Burlington Group, and is so far removed from all 

 others that no comparison with any of them is necessary. 



Found by C. S. Hodgson in the Burlington Group, in Adams 

 County, Illinois, and now in the collection of S. A. Miller. 



BATOCRINUS FOLLICULUS. n. Sp. 



Plate I, Fig. 36, azygous view; Fig. 37, opposite side; Fig. 38, 



summit view. 



Species medium or below medium size and ovoid in outline. 

 Calyx broadly rounded below and contracted above the third 

 radials so as to make it somewhat globular. The length is 

 about equal to the diameter at the bases of the arms, but the 

 greatest diameter is below, in the region of the third primary 

 radials. Plates convex and sutures distinct. No radial ridges. 

 Surface finely granular. Column small. 



Basals form a very low hexagonal disc, which expands up- 

 ward and is concave below for the reception of a small column 

 The basals are so short that they hardly interrupt the general 

 globular form of the calyx below. First primary radials rap- 

 idly expand and with the radials form a low saucer-shaped 

 cup. Their length is nearly equal to their breadth, three hex- 

 agonal and two heptagonal. Second primary radials, quadran- 

 gular, and from one-half wider to twice as wide as long. Third 

 primary radials very little if any larger than the second, pen- 

 tagonal, axillary, and support on each superior sloping side 

 two secondary radials. There are, therefore, ten arms in this 

 species. 



The first regular interradials are large, convex plates. There 

 are two plates in the second range, one of which is elongated 

 and in some of the areas appears to connect with a plate be- 

 longing to the vault, and, in other areas, the last secondary 

 radials appear to unite and cut off the interradial area. The 



