pest a calla 
420 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
Horizon and Locality.—In the Keokuk group at Bono, Indiana, and at 
Keokuk, Iowa. Also in the Warsaw limestone at Spergen Hill, Ind., and at 
Glasgow, Barren Co., Ky., and Boonville, Mo. 
Types in the collection of Wachsmuth and Springer. 
Ltemarks.— Miller’s Batocrinus spergenensis was described from a speci- 
men of Dizygocrinus Whitei in which the surface markings were eliminated 
by weathering. Specimens of this kind occur frequently at Spergen Hill, 
while well preserved specimens are rare. 
Dizygocrinus Whitei, var. didactylus W. and Sp. 
Plate XX XV. Figs. 12, 128. 
About the same size as the typical form, but the arms considerably 
thinner, and there are two arms to each opening when perfectly developed, 
which, however, is rarely the case. The radials and fixed brachials are trav- 
ersed longitudinally by a strong, angular ridge. The arms are given off 
from a minute axillary in the usual way, and are slender, long, and infolding. 
Horizon and Locality. —Uppermost part of the Keokuk group; Hamil- 
ton, Ills. 
Types in the collection of Wachsmuth and Springer. 
Dizygocrinus decoris (S. A. Mituzr). 
Plate XXX V. Fig. 6. 
1891. Batocrinus decoris —S. A. Mitimr; Adv. Sheets 17th Rep. Geol. Surv. Indiana, p. 61, Plate 10, 
Figs. 7 and 8. 
Calyx of medium size, a little wider than high. Dorsal cup low saucer- 
shaped, less than half the height of the ventral disk. Plates of the dorsal 
cup barely convex, their surfaces covered with numerous minute irregular 
pustules, and the radials and costals marked by small angular ridges, which 
from the basals pass up to the arm bases. The sutures very slightly grooved. 
Basals quite short, anchylosed, and no suture lines visible; they merely 
consist of a thickened circular rim, which projects slightly over the top of 
the column. Radials and costals very short, both fully three times as wide as 
long. The costals support 2 X 2 distichals, and these three rows of palmars, 
of which the upper supports the arms, except sometimes in the anterior 
ray, which occasionally only has two arms given off from four successive 
distichals. All distichals and palmars are comparatively wide and very 
short, the latter in contact laterally. Arm facets nearly equidistant, large, 
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