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706 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
Platycrinus pocilliformis Hatt. 
Plate LX VIL, Figs. 2a, b. 
1858. Hat; Geol. Rep. Iowa, Vol. I., Part II., p. 528, Plate 8, Figs. 2a, 
1881. W. and Sp.; Revision, Part II., p. 74 (Proceed. Acad. Nat. Sci. Phila., p- 248). 
A little shorter than the preceding species. Calyx to the top of the 
radials cup-shaped, wider than high ; the height of the basals equal to nearly 
one third the length of the cup; the sides very slightly expanding to the 
middle, the upper ends at right angles to the base of the cup; the suture’ 
lines not grooved. Surface of plates marked by rather short, rounded 
nodes, which upon the basals are arranged in double or triple rows, a row 
_ of three extending from the column facet to the upper angles. The radials 
generally have a row of four or five nodes running from the radial facet 
to the lower angles of the plates, which enclose four or five others, and there 
are three or four at each side. 
Basals forming a flat, pentagonal cup; the column facet small and barely 
unpressed; the interbasal suture lines indistinguishable. Radials a little 
wider than long, quadrangular, the upper face constituting an almost 
straight line ; facets small, directed obliquely upward, restricted to the 
upper ends of the plates, and occupying but one third their width. 
Arms apparently five to the ray, and ornamented with small nodes. 
Horizon and Locality. — Lower Burlington limestone, Burlington, Towa. 
Lype in the (Worthen) Illinois State collection, Springfield. 
ftemarks. — Differing from P. verrucosus in the shorter calyx, in having 
less prominent, and differently arranged nodes, and in the ornamentation of 
the arms. 
Platyerinus Yandelli 0. and Su. (typical form). 
Plate LXVI. Figs. 6a, b, c; and Plate LXVIII. Figs. 8a, b, e. 
1852. Owxn and Suumarp; U.S. Geol. Rep. Wisc., Iowa and Minn., p. 587, Plate 54, Figs. 6a, 4, e. 
1881. W.and Sp.; Revision Paleocr., Part II., p. 76 (Proceed. Acad. Nat. Sci. Phila., p. 250). 
Of medium size. Dorsal cup low cup-shaped, obscurely pentangular from 
a dorsal view, the interradial suture lines forming the angles; the sides 
nearly straight, slightly expanding. The radial facets almost in the same 
plane with the surface of the plates, and unusually large, occupying fully 
half the length of the plates and two thirds their width. Surface of basals 
