tinguished from Baiocrinus is found in the arms, and, as we shall 

 have occasion to describe a species, in this paper, having the flat- 

 tened arms belonging to Eretmocrinns, we will defer further com- 

 parison until that species is before us. If Eretmocrinus, however, 

 is a valid genus, the probability is, that this species should be re- 

 ferred to it, in the absence of a knowledge of the arms, for, oth- 

 erwise, the genus can only be known by the arms, which are 

 rarely ever found, in chert or among silicified specimens. The 

 species most nearly related to this one is Ereimoerinus lyonanus, 

 though they are readily distinguished by the basal plates and in- 

 to radial areas; differences, however, which are only specific, not 

 generic. They both belong to the same genus. 



Found by Prof. A. G. Wetherby, in the Keokuk Group, at 

 White Creek Springs, Tennessee, and now in the collection of. 

 Wm. F E. Gurley. 



BATOCRINUS LACINIOSUS, n. Sp. 



Plate 1, Fig. 15, view opposite the azygous area; Fig. 16, azy- 

 gons side of same specimen. 



Species medium size, one of our specimens is much smaller than 

 the one illustrated. General form biturbinate; vault larger than 

 the calyx. Calyx twice as wide as high, broadly truncated below 

 aud rapidly expanding from the secondary radials so as to direct 

 horizontally the last tertiary radials and ambulacral openings. 

 Plates on the lower part of the calyx tumid and subspinous, those 

 on the superior part plane or slightly convex. Radial ridges un- 

 defined; sutures distinct. 



Basals form a low hexagonal disc, one-half wider than the 

 diameter of the column. Columnar depression concave and radi- 

 ately furrowed, canal small. First primary radials large, only a 

 little wider than long and each bears a robust, transverse, cunei- 

 form node, three hexagonal, two heptagonal. Second primary 

 radials very small, short, about twice as wide as long, quadrangu- 

 lar. Third primary radials about one-half larger than the second, 

 pentagonal, axillary, and in the rays adjoining the azygous area, 

 bearing on the distal sloping sides three secondary radials and on 

 the proximal sides one secondary radial, which is axillary, and 

 bears upon its superior sloping sides three tertiary radials, which 

 gives to each of these rays three arms. Jn the two lateral rays 

 the third primary radials bear upon each superior sloping side a 

 single secondary radial, which is axillary and bears upon each 

 upper sloping side three tertiary radials, which gives to each of 



