Silt T0007. NEw CrINoIDS — SLOcom. 285 
are the smallest and are not in contact with the posterior one; anus 
unknown; five groups of arms are situated where the interoral sutures 
meet the radials. The distal edges of the radials are thickened on their 
inner side and are pierced by pores. The presence of these pores has 
been taken by some writers to indicate that the genus might belong 
to the cystoids, but for the present it is considered to be a crinoid. 
ZOPHOCRINUS GLOBOSUS sp. nov. Plate LXXXV, Figures 15-19. 
The calyx is small, in the form of a prolate spheroid, truncated at 
the top. The natural casts are subspherical, slightly flattened on six 
sides, approaching a rounded hexahedron. The plates are rather thick 
and smooth or possibly finely granulose, convex, slightly sloping towards 
the sutures, so that their shape and arrangement is easily studied. 
Basal plates three, much thicker than the radials; two are quad- 
rangular and about equal in size; the other is pentangular and larger; 
together they form a shallow rounded cup with aslight triangulation at 
the base and a circular depression for the reception of the column. 
Radials four, height and width about equal; three are pentangular, the 
other is quadrangular; their sides are subparallel, slightly contracted 
at either end. These plates have a decided thickening of the inner 
margin of their distal ends, which is shown by a deep groove on the 
natural casts. The ventral disc is not preserved on any of the spec- 
imens studied. 
The species differs from the other species of the genus 1n its globose 
form, its relatively short radial plates and its rounded base, as com- 
pared with the pear-shaped body and attenuate obconical base of the 
other species. These characters are stated in more detail on a later 
page. 
Locality: Niagaran limestone of the spoil heaps along the Drainage 
Canal, about a mile and a half east of Lemont, Illinois. 
This species, while it cannot be said to be abundant in this Area, is 
by no means rare. Four specimens were collected by the writer in the 
fall of t905 and a like number in the spring of 1906. The specimens 
consist of natural casts with more or less of the accompanying molds. 
The Museum number of the type specimen is P 8480. 
ZOPHOCRINUS PYRIFORMIS sp. nov. Plate LXXXV, Figures 12-14. 
The calyx is broadly pear-shaped, truncated at the top, expanding 
rapidly from the base to about the middle of the radials, from which 
point it contracts to the arm bases. The surface of the plates is finely 
granulose and moderately convex, sloping towards the sutures; this 
shallow depression indicates the position of the sutures. 
