58 
SMITHSONIAN INSTITUTION 
Basal pentagon proportionally larger; surface ornament similar but usually less 
pronounced. Radial facets directed above the horizontal. Tegmen plates raised, 
somewhat nodose, angular, or smooth ; ambulacra fairly defined. 
Roemer’s P. tcnnesscensis as described bv him contains two species, of which his figures 
4a, h, c, must be taken for the type. His specimen was weathered, and surface of both cup 
and tegmen probably eroded. But the characters above specified are sufficient to identify the 
species, of which Wachsmuth and Springer figured a well preserved example (N. A. Crin. 
Cam., pi. 75, fig. 16, but not fig. 17). 
Horizon and locality. Beech River formation, Brownsport group, Niagaran; Eucalypto- 
crinits zone and glades, Decatur County, Tennessee. 
Marsipocrinus striatus (Wachsmuth and Springer) 
Plate T4, figs. 7-jy 
Marsupiocrinus striatus Wachsmuth and Springer, N. A. Crin. Cam., 1897, p. 732, pi. 75, fig. 18 only. Not 
Cupellaecrinus striatus Troost, nor Marsipocrinus striatus, Wood, Bull. 64, U. S. Nat. Mus., 1909, 
p. 33, pi. 9, figs. 13, 14 — M. inflatus. 
A somewhat smaller species than the preceding, varying from 12 to 14 mm. 
height of calyx to 15 to 26 mm. diameter. Calyx bi-convex, dorsal cup usually 
higher than tegmen. Basal pentagon shallowly depressed, about one half the 
total width. Radial facets directed upwards. iBr usually not projecting, smooth, 
curving over edge of tegmen. Tegmen lo\v, plates rounded, smooth and but 
little raised, leaving ambulacra well defined. Surface of cup usually striate, 
continuous from plate to plate, sometimes rather corrugate with striae more 
obscure — much dependent upon preservation. 
A considerable number of specimens answer to this description, and agree fairly well 
with the type of Wachsmuth and Springer, pi. 75, fig. 18. It is a variable form, tending to 
shade into other species, but the strong striate ornament and prominent exposure of ambu- 
lacra are the features chiefly relied on. In specimens from the glades the striae are usually 
much obscured by weathering, for which allowance must be made. 
Horizon and locality. Beech River formation, Brownsport group, Niagaran; Tuck’s 
Mill and on glades, Decatur County, Tennessee. 
Marsipocrinus inflatus (Troost) 
Plate 15, figs. 1-8 
Cupellaecrinites inflatus Troost, Proc. Am. Assn. Adv. Sci., 1850, p. 61. — Marsupiocrinus striatus, 
Wachsmuth and Springer, N. A. Crin. Cam., 1897, pi. 75, fig. 17. — Wood, Bull. 64, U. S, Nat. Mus., 
1909, p. 34. 
A fairly large species, with calyx relatively high, the average being about 
20 mm., by 30 mm. wide. Dorsal cup convex and rather deep; basal pentagon 
large, about three fifths the total diameter, margins usually notched at the inter- 
basal sutures, and sometimes with slight protrusions at the middle of the sides. 
iBr not projecting, but flush with calyx wall and curving over into the tegmen. 
