BATOCRINID&. Swi 
Batocrinus equalis (Hatz). 
Plate: XX VAT, Vigs25,0: 
1858. <Actinocrinus equalis —Ha1; Geol. Rep. Iowa, Vol. I., Part IT., p. 592, Plate 11, Figs. 4a, 0. 
1873. Batocrinus equalis—M. and W.; Geol. Rep. Illinois, Vol. V., p. 367. 
1881. Batocrinus equalis —W. and Sp.; Revision Paleocer., Part II., p. 165. 
Syn. Actinocrinus doris — Haut, 1861; Deser. New Spec. Crin., p. 15. 
Syn. Batocrinus doris — M. and W.; Geol. Rep. Illinois, Vol. V., p. 367. 
Closely allied to the preceding species, but differing in the greater 
number of arms. Calyx biturbinate, truncate at the bottom; the dorsal 
cup a little higher than the ventral disk; the sides abruptly spreading to 
the arm bases, which are directed horizontally ; the plates smooth, highly 
convex. 
Base short, excavated for the reception of the column, the interbasal 
sutures deeply grooved, giving to the lower end a trilobate outline. Radials 
smaller than the basals, from once and a half to twice as wide as long. First 
costals less convex than the surrounding plates, quadrangular, variable in 
size, sometimes but half the width of the radials and very short. Second 
costals wider and longer than the first. Distichals 22; supporting in 
four of the rays two rows of three plates, and these four arms to the rays. 
In the two posterior rays, which have from six to seven arms, both outer 
distichals of the rays support an axillary palmar, which is followed by 2X 2 
post-palmars ; while the two inner distichals support but 2 palmars. When 
there are seven arms, one of the post-palmars is also axillary and gives off 
two arms instead of one. Arms short, cylindrical, biserial from their bases ; 
the plates short. Pinnules long. Regular interbrachials two or three, the 
first very large. The anal area consists of five plates; the anal plate, which 
is larger than the radials, is succeeded by three plates in the second row, and 
a small piece above. At all sides the interbrachial plates are separated from 
the dome plates by the palmars, and post-palmars respectively, which form 
together with adjoining distichals and costals around the plates of the anal 
area a well defined semicircle. Ventral disk conical, gradually passing into 
the anal tube; the plates strong and convex. The orals and ambulacral 
plates are much larger than the intervening ones, which latter are com- 
paratively small and numerous at the posterior side. Anal tube central, 
its plates slightly tumid. Column similar to that of the preceding species. 
Horizon and Locality.— Lower Burlington limestone ; Burlington, Iowa, 
and Southern Missouri. 
Type in the (Worthen) Illinois State collection, Springfield. 
