34 



bears upon each upper side, a single tertiary radial, which 

 gives to this ray three arms. There are, therefore, nineteen 

 arms in this species. 



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

 followed by two smaller ones, below the tertiary radials, which 

 abut against each other and cut off the area from any connec- 

 tion with the vault. There are seven plates in the azygous 

 area. The first one in the line with the first primary radials 

 and somewhat narrower; it is followed by three plates in the 

 second range and two in the third and above these one plate 

 that unites with the plates of the vault, as it appears in our 

 specimen. Our specimen, however, is slightly injured about 

 the top of this plate, so as to leave the sutures in doubt, and 

 possibly an angle from the tertiary radials may separate it 

 from the plates of the vault. 



The vault is somewhat pyramidal in the lower part and 

 conoidal above. On the azygous side there is a longitudinal, 

 concave depression extending down to the azygous area of the 

 calyx. The vault is covered with slightly convex, polygonal 

 plates. The proboscis is large and central. There are no 

 ovarian pores. 



This species is distinguished by its general form and nine- 

 teen ambulacral openings to the vault. It is unnecessary to 

 compare it with any other species that possessed the same 

 number of ambulacral openings. 



Pound by S. A. Miller, in the Keokuk Group, at Boonville, 

 Missouri, and now in his collection. 



BATOCRJNUS VICINUS, n. sp. 



Plate IT, Fig. 1, basal view; Fig. 2, azygous side view; Fig. 3, 



summit view. 



Species below medium size, vault rather larger than the 

 calyx, but, on the whole, somewhat trochiform. Height of the 

 calyx less than half the diameter, and ambulacral openings di- 

 rected horizontally. Radial series project at the margin so as 

 to notch the circumference at the interradial parts. Radial 

 ridges moderately well defined and angular, Surface, granu- 

 lar. Column round and small. 



