Description of New Genera of Echinodermata. 19 
which gives breadth to the area between the third radials and the 
brachial plates; the column is round and composed of alternately 
thicker and thinner plates. Our specimens do not show the vault. 
This is a beautiful little species, quite different from any hereto- 
fore described, and occurs in the Keokuk Group, at Crawfords- 
ville, Ind. It is in the collection of Wm. F. E. Gurley. 
BATOCRINUS MARINUS, N. Sp. 
Flate LV., Fig. 3, side and basal view ; Fig. 4, outline view of plates on 
azygous side. 
Species of about the average size; calyx expanded at the arm 
bases so as to be wider than high and to make the openings through 
the vault from the arm furrows at right angles to the calyx; surface 
of the plates flattened and finely granulous; basals three, upright 
and forming a circle which appears as if it were the enlarged end 
of the column; first radials wider and larger than the second and 
third together, three heptagonal and two hexagonal; the upper face 
is truncated for the second radial, and the upper sloping sides sup- 
port the first interradials; second radials quadrangular, a little 
wider than high; third radials wider than the second but not 
longer, pentagonal or hexagonal, the lower lateral sides spreading 
so as to give the greatest width at the angles made with the upper 
sloping sides; the upper sloping sides support the secondary 
radials; secondary radials two by ten, wider than long, somewhat 
variable in size and shape, the second one bearing upon its upper 
sloping sides a single tertiary radial; the tertiary radials are suc- 
ceeded by a double series of interlocking arm plates; arms twenty, 
rather small, slender, gradually tapering and composed of a double 
series of plates, alternately interlocking; in our specimen they are 
coiled together on the vault around the base of the proboscis; pin- 
nules very numerous. Regular interradials five, the first one 
polygonal, about as large asa first radial and nearly as large as 
the other four; the first one 1s followed by two plates and these by 
two which are between the second secondary radials and the upper 
sloping sides of the tertiary radials; there is one intersecondary 
radial in each area; azygous interradials nine, the first one in line 
with the first radials and of the same size, this is followed by three 
smaller ones, and these again by three, and these by two which fit 
