630 STUART WELLER 
and consequently in the somewhat less divergent sides, also in the 
shallow concavity of the underbasal disk and in the longer lateral 
faces of the basal plates. 
ERISOCRINUS TRINODUS N. Sp. 
(Plate I, Figs. ro, 11) 
Description.—Dorsal cup turbinate, the sides nearly straight, diver- 
ging from the base at an angle of a little less than go°, the sutures 
between the plates flush with the general surface, not situated in 
depressed grooves. The dimensions of the type specimen are: 
diameter of dorsal cup 14.5™™, height of same g™™. Underbasal 
plates five, less than one-half of their proximal extremities covered 
by the columnar facet, the exposed portions of the plates smooth, 
forming the flaring sides of a shallow cup. Basal plates smooth, 
wider than high, hexagonal in outline, their distal extremities angular, 
the two distal faces longer than any of the others, the two proximal 
faces meeting in an angle so obtuse that the two together make 
nearly a straight line. Radial plates much wider than high, pen- 
tagonal in outline, the surface curving inward toward the distal mar- 
gin, each bearing three distinct nodelike tubercles symmetrically 
arranged, one near each lateral margin of the plate with the third 
situated lower down on the median line of the plate. No anal plate 
present. 
Remarks.—This species is based upon a single nearly complete 
but somewhat weathered dorsal cup. In general shape it resem- 
bles E. conoideus M. and W., from the Pennsylvanian at Springfield, 
Ill., but it is much larger and is characterized by the presence of the 
three nodelike tubercles upon each radial plate. 
CIBOLOCRINUS Nn. gen. 
Description.—Dorsal cup basin-shaped or turbinate. Underbasal 
plates three, two large and one small, the larger plates formed by 
the fusion of the right and left pairs. Basal plates large, the anterior 
pair hexagonal in outline, the right and left postero-lateral ones 
pentagonal, the posterior one heptagonal. Radial plates large, 
wider than high, pentagonal in outline, the distal faces supplied with 
strong, articular ridges. Anal plate small, resting between the 
