292 FreLtp CoLtumMBIAN Museum — Geo oey, Vot. II. 
Locality: Collected by the writer in the spoil heaps along the 
Chicago Drainage Canal about 1% miles east of Lemont, Illinois. (Mus. 
No. P 8887.) 
Family CROTALOCRINIDZ!. 
CROTALOCRINUS Austin. 
CROTALOCRINUS CORA Hall, Plate LX X XVI, Figs. 3 and 4. 
1868 Cyathocrinus cora Hall, 20th Rept. N. Y. St. Mus., p. 324, Pl. 
XG FigssisetA: 
1870 Cyathocrimus cora Hall, 2oth Rept. N. Y. St. Mus. (Rev. 
Edy). p. 3266, eP iA Xl Sige tana 
1879 Cyathocrinus cora W. & Sp., Rev. Paleocrin., Pt. I, p. 85. 
1881 Cyathocrinus cora S. A. M., Jour. Cin. Soc. Nat. Hist., Vol. 
LV te | 
1900 Cyathocrinus cora Weller, Bull. 4, Nat. Hist. Surv. Chicago 
Acad. Sci., p. 62, Pl. XIV, Figs. 6-10. 
tg00 Crotalocrinus americanus Weller, ibid. p. 143, Pl. XIV, Fig. 1. 
1902 Crotalocrinus cora Weller, Jour. Geol., Vol. X, p. 532, Pl. ILI. 
This species is abundant at various localities in the vicinity of 
Chicago and at Racine, Wisconsin, in the form of natural casts, but it 
is rarely found with the brachial plates preserved. The specimen here 
figured (Mus. No. P 8809) shows the anterior and right anterior rays, 
complete to the fourth bifurcation of the brachials, and part of the left 
anterior and right posterior rays. This is probably the most complete 
specimen of this species yet discovered: .The specimen consists of a nat- 
ural cast with more than half the accompanying mold. Fig.3 1s drawn 
from a “‘composition’’ impression taken from the natural mold. Col- 
lected by the writer in the upper layers of the Hawthorne Quarry, Chi- 
cago, May, 1906. 
Order III]. CAMERATA. 
Family PLATYCRINIDA. 
PLATYCRINUS Miller. 
PLATYCRINUS AUGUSTA sp. nov. Plate LXX XVI, Figures 5—7. 
Dorsal cup subhemispherical, sharply constricted above, with the 
base produced into a circular facet for the attachment of the column. 
Pentangular in transverse section at the arm bases, circular below. 
Plates thin, without ornamentation, conforming to the curvature of 
the calyx; sutures not in furrows, inconspicuous. 
