17 



tertiary radials, at the angles between the two vault plates, in 

 the azygous depression, and the smaller plate at each side of 

 the ambulacral canals. Proboscis unknown. 



Found in the Keokuk Group at Boonville, Missouri, and 

 now in the collection of S. A. Miller. The specific name is in 

 honor of Prof. G. C. Broadhead, formerly State Geologist of 

 Missouri, a gentleman of high scientific attainments, whose 

 professional skill and untiring energy has to such a great 

 extent contributed to our knowledge of the geology, as well as 

 to the wonderful development of the mining and economical 

 industries of that state. 



BATOCRINUS NITIDULUS, n. Sp. 



Plate I, Fig. 12, azygous view of calyx and vault; Fig. 13, 

 opposite view of same. 



We have four specimens of this species of the same size and 

 in the same state of preservation as the one illustrated. None 

 of them show any of the arms. 



Species below medium size. Calyx broadly truncated below 

 and obconoidal above, or like the frustum of a cone; one-half 

 wider than high. Plates convex, usually bearing a transverse 

 angular ridge, and beveled from the central part to the su- 

 tures. No radial ridges. Column small and having a very 

 small, round, columnar canal. 



Basals form an hexagonal disc nearly twice as wide as the 

 diameter of the column and having a height less than half the 

 diameter of the column. First primary radials wider than high. 

 Second primary radials quadrangular, about three times as 

 wide as high. Third primary radials vary from pentagonal to 

 heptagonal depending upon the number of interradials that each 

 side abuts against, and they vary somewhat in size, but are 

 about twice as large as the second radials, axillary, and sup- 

 port on each upper sloping side two secondary radials, the 

 last one of which is axillary and supports on each upper slop- 

 ing side a single tertiary radial. There are, therefore, four 

 arm openings to the vault from each ray or twenty ambulacral 

 openings to the vault. The probability is that the arms did 

 not bifurcate and that the species had only twenty arms. 



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



the other two smaller and somewhat elongated, ir. the speci- 

 —3 



