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HEXACRINID. 81 ¢ 
side inward. Both horns of the crescent give off cirri from alternate plates, | 
communicating with the axial canal of the stem, which is oval, its long dia- I 
meter at right angles to the curvature of the column. There are no cirri in ) 
the upper part of the stem; they commence at some distance from the calyx, | 
and are restricted to the convoluted part. In specimens with a closely coiled i 
stem, the ends of the cirri meet in the centre, and resemble the spokes of a | 
wheel; they are stout at the proximal end and extremely long, being com- 
ies) 
posed of thirty or more pieces, of which the five proximal ones are longer 
than wide, the upper somewhat shorter. 3 
Horizon and Locality. — Kaskaskia group, near Sloans Valley, Pulaski | | 
Co., Ky. 
Types in the collection of Wachsmuth and Springer. 
TALAROCRINUS W. and Sp. 
1881. W. and Se.; Revision Paleocr., Part II., p. 85-(Proceed. Acad. Nat. Sci. Phila., p. 259). 
1883. §S. A. Mitzer; Catal. Amer. Paleeoz. Foss. (Second Edit.), 288. 
1885. W. and Sp.; Revision Paleeocr., Part III., p. 120 (Proceed. Acad. Nat. Sci. Phila., p. 342). 
1889. §. A. Minter; N. Amer. Geol. and Paleont., p..285. 
Syn. Dichocrinus (in part) —Suumarp; Trans. St. Louis Acad. Sci., Vol. I, p. 71. 
Syn. Dichocrinus (in part) — Cass. and Lyon; Proceed. Amer. Acad. Artis and Sci., pp. 16-28. | 
Syn. Prerotocrinus (in part) —S. A. Minter; Catal. Amer. Paleeoz. Foss. (First Hdit.), p. 89. | 
Specimens small. Calyx, as a rule, higher than wide; the ventral disk 
as high as the dorsal cup; the plates thick and devoid of ornamentation. 
Basals two, of equal size and similar form, the suture between them | 
passing from the anal plate to the anterior radial; they form together 
a shallow cup, which is more or less transversely elongate, and somewhat 
) 
excavated at the bottom; the superior margin of the cup octagonal, six : 
angles being salient and two retreating, the latter directed to the sides 
which correspond to the longer diameter of the base. : 
Radials five, enclosing an anal plate of the same size or even larger; four 
of them having slightly convex lower faces; while the anterior one is angular 4 
below. The upper faces are somewhat excavated in the middle, and trun- : 
cated at the outer ends. Costals one, very small, often completely hidden : 
from view by the distichals ; when visible, triangular in outline. Distichals 
one or two, small; their lower faces resting obliquely against the costals; 
their sides touching the radials. The third order of brachials supports the 
free arms, of which there are four to the ray. The arms, so far as observed, lf 
SS — = ——— 
are simple and biserial. 
