BATOCRINIDiE. 373 



convex ; the suture lines grooved. Basals short, thickened around their 

 lower margins, and slightly excavated for the attachment of the column. 

 Eadials a little wider than long, concave at the upper face. Costals com- 

 paratively larger than in the preceding species ; quadrangular and pentangu- 

 lar ; the second wider than the first. Distichals two (except toward the anal 

 side) ; the upper wider than the costal axillary ; followed by two palmars, of 

 which the second is the larger. Toward the anal side there is but one dis- 

 tichal, and the second palmar at the outer divisions of the rays supports two 

 post-palmars, but only one at the inner side, making five arms to each of the 

 posterior rays. Arm openings arranged at nearly equal distances ; directed 

 horizontally. Respiratory pores large, placed a little above the arm bases. 

 Arms heavy, short, slightly flattened on the back ; composed of two series 

 of short joints. Interbrachials two ; the first extending to the lower sloping 

 faces of the first distichals. The palmars in lateral contact except at the 

 posterior side, where only the post-palmars connect laterally. Anal plate 

 longer than the radials ; followed by three and two plates. The plates of the 

 ventral disk vary in size ; the orals and radial dome plates being more than 

 twice as large as the intervening pieces, which are quite numerous. Length 

 of anal tube not known. 



Horizon and Locality. — Lower Burlington limestone ; Burlington, Iowa 

 and Southern Missouri. 



Type in the (Worthen) Illinois State collection. 



Batocrinus Calvini Rowley. 

 Plate XLVI. Figs. 8a, h. 



1890. Rowley; Amer. Geologist, Vol. V., p. 146. 



Calyx greatly depressed, almost twice as wide as high, with a sharp edge 

 around the margin. Dorsal cup low bowl-shaped, a little higher than the 

 ventral disk. Plates very slightly convex ; the suture lines distinct, but not 

 actually grooved. 



Basals quite small, forming a pentagon without re-entering angles ; the 

 columnar concavity narrow but rather deep. Radials as large as both cos- 

 tals together, wider than high. First costals quadrangular, twice as wide as 

 high ; the second pentangular, wider than the first, but narrower than the 

 radials ; the upper angle quite obtuse. Distichals larger than the costals ; 

 represented in four of the rays by two series of two plates, the upper ones, 



