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PLATYCRINIDZ. 
Cordylocrinus plumosus (Ha11). 
Plate LXXV. Fig. 20. 
1859, Platycrinus plumosus — Haus ; Paleont. New York, Vol. IIL, p. 113, Plate 4, Figs. 1 to 5. 
1881. Cordylocrinus plumosus —W. and Sr.; Revision, Part II., p. 60 (Proceed. Acad. Nat. Sci. Phila., 
Syn. gene parous — Hat; Paleont. New York, Vol. IIT., p. 114, Plate 4, Figs. 6 to 9. 
Syn. Cordylocrinus parous— W. and Sp.; Revision, Part II., p. 60. 
A small species. Dorsal cup subpentangular, expanding to the arm 
bases; surface of plates finely granulated. Basals very thin, wider than 
Jong, the column facet small. Radials excavated for the reception of the 
costals. The three radials meeting an interbasal suture distinctly angular 
at the lower end, the two others nearly straight. The upper faces of those 
adjoining the anal side forming a deep notch, occupied by a large pentan- 
gular plate, which is succeeded by a smaller plate forming the base of a 
proboscidiform tube (Hall, Plate 4, Fig. 3). Costals two. Arms two to the 
ray, composed of transverse, slightly wedge-form pieces, giving off large 
pinnules, which are not in contact laterally, Column composed of nodal — 
and internodal joints, the latter rapidly increasing in number, the nodal 
joints giving off whorls of cirri, one to each side, interradially arranged. The 
cirri are formed of short pieces; they are filiform and directed upwards, 
often so long that the tips of the proximal ones pass up to the top of the 
arms. 
Horizon and Locality.— Lower Helderberg group; Schoharie, Herkimer 
Con Ne Ye 
fiemarks. — We have not examined Hall’s types, but doubt if they show 
much more of the structure. The form which Hall described as Platycrinus 
porvus 18 mn our opinion a younger form of Cordylocrinus plumosus. 
(?) Cordylocrinus ramulosus (Hat).* 
1858. Platycrinus ramulosus — Hau ; Paleont. New York, Vol. III., p. 115, Plate 4, Figs. 10 to 13. . 
1881. Cordylocrinus ramulosus — W. and Sv.; Revision, Part II., p. 60 (Proceed. Acad. Nat. Sci. Phila., 
p. 234). 
Dorsal cup small. Basals wider than long. Radials comparatively large, 
wider than long, very prominent below the facets, and contracted toward 
12, 
the upper lateral angles. Costals two, very small. Arms bifurcating from 
* This species may belong to a very different group. It was apparently described from very imperfect 
specimens, and not having seen the types, we give Hall’s description with our terminology. 
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