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| 772 ‘THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
Dichocrinus Ulrichi Mituer and Gurtey. 
1890. Journ. Cincin, Soc. Nat. Hist., Vol. XIII. (Author’s Ed., p. 48), Plate 8, Figs. 12 and 13. 
A small species. Calyx subovoid, once and a half as high as wide, 
somewhat constricted at the upper end, pointed at the lower; the plates 
smooth. Basals large, forming a high obconical cup, with a deep notch at 
the anal side; the column facet small. Radials nearly twice as long as wide, 
spreading upwards, reaching their greatest width at three fourths their 
height, contracting at the upper end; the sides slightly depressed, leaving 
the sutures rather distinct; facets narrow, and occupying but one third the | 
width of the radials. Costals two, apparently united by syzygy, as well as | 
the two proximal distichals, both being so closely united that the lines are 
frequently invisible. Arms two to the ray, rather long and comparatively 
stout; they are composed of single joints, of which the upper and lower 
edges are almost parallel, and not so decidedly cuneate as figured by Miller 
and Gurley. Pinnules coarse, long, and closely packed. First interbrachial 
plates visible in a side view. Anal plate a little longer and narrower than 
the radials. 
florizon and Locality. — Upper part of the Keokuk group; Bono, Law- 
| | rence Co., Ind. 
Type in the collection of Wm. F. E. Gurley. 
Remarks. —'This species resembles so closely Dichocrinus scitulus from 
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the Upper Burlington limestone, that we doubt if the two forms represent 
im) different species. We find it impossible to separate them in our collection, 
in which we have specimens from both horizons. | 
if W | Dichocrinus Hamiltonensis Worruen. | 
Plate LX XVI. Fig. 10. 
1882. Bulletin I., Illinois State Museum Nat. History, p. 35. 
1883. Geol. Rep. Illinois, Vol. VIL., p. 318, Plate 27, Fig. 10. 
—_— 
A little larger than the preceding species. The specimen from which the 
description was made, and the only one known to us, is badly crushed, and 
the exact proportions of the calyx cannot be given. From its appearance, 
however, we take the length of the dorsal cup to be about equal to its width, 
and the height of the basals about half that of the radials. The latter are 
subquadrangular, narrower at the lower end, the length equal to their 
