458 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
Keokuk, and generally crushed. Good calyces are found in Barren Co., 
Ky., and very excellent specimens with arms came from Indian creek, Mont- 
gomery Co., Ind. 
Type in the (Worthen) Illinois State collection, Springfield. 
ftemarks. — it is only in very large specimens that every arm is paired, 
single arms being most generally represented in one or more rays. It is also 
interesting to note that our largest specimen not only has the arms all in 
pairs, but has in both antero-lateral rays four pairs instead of three, — the 
only exception among seventeen specimens. 
Dorycrinus cornigerus (Hatt). 
Plate XLII. Figs. 5 and 6, and Plate XLT. Fig. 5, and Plate XLIV. 
Figs. 6 and 7. 
1858. Actinocrinus cornigerus — Hau; Geol. Rep. Iowa, Vol. I., Part II., p. 576, Plate 9, Figs. 12a, 8, ¢, 
and ibid., Suppl., Plate 3, Fig. 4. 
(Not Actinocrinus cornigerus Lion and Cass., 1859 = Aorocrinus kentuckiensis). 
1873. Doryerinus cornigerus— MerKx and WortHEN; Geol. Rep. Illinois, Vol. V., p. 880. 
1881. Dorycrinus cornigerus —W. and Sp.; Revision Paleocr., Part If., p. 179 (Proceed. Acad. Nat. Sci. 
Phila., p. 358). 
Syn. Actinocrinus divaricatus Hatt; 1859, Suppl. Geol. Rep. Iowa, p. 11. 
Syn. detinocrinus decornis Hari; 1859, ibid., p. 13. 
Calyx wider than high; the ventral disk as high as the dorsal cup. The 
latter turbinate, broadly truncated at the base, spreading rather rapidly from 
the top of the basals to the top of the costals,and thence more abruptly to 
the arm bases. The distichals and palmars form very prominent lobes with 
well defined sinuses between the arm-bearing plates. Plates smooth and 
almost flat, the suture lines but very slightly grooved. 
Base large, the rim almost circular and without notches at the sutures; 
almost flat on the bottom, the column facet occupying but one fourth of its 
diameter. Form of radials variable; in some specimens almost as long as 
wide, in others nearly twice as wide as long, the upper face excavated. Cos- 
tals rather large; the first quadrangular, once and a half as wide as long, the 
lower face convex ; the second wider but not longer than the first; the sides 
spreading abruptly upwards; the three anterior ones generally heptangular, 
those facing the posterior side hexangular, the sloping upper sides straight, 
contrary to those of D. gwinquelobus, in which they are excavated. The pos- 
terior rays, and occasionally the anterior one, have two axillary distichals, 
which on each side support a moderately long palmar, the latter ray in the 
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Seen 
