PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. JD ( 



thick and often massive. This delicacy of structure is probably a ge- 

 neric characteristic. 



Lecythiocrinus oUiculaeformis (sp. nov.). Plate 1, figs. 4 aud 5. 



Body small, subovoid or pot-shaped, higher than broad, broadest a 

 little below the middle, composed of thin pieces ; base convex ; basal 

 pieces rather small but not minute; subradial pieces larger than any of 

 the others, higher than wide, their height equal to a little more than 

 half the full height of the body, not materially varying in size or 

 shape ; first radial pieces smaller than the subradials but larger than 

 the basals, broader below than above, height and greatest breadth about 

 equal ; at top, on both sides of the small prominent arm -facet, the 

 border of each first radial is bent inward, constricting the already nar- 

 row interbrachial space at the top of the body, which space was prob- 

 ably covered by a dome of minute pieces. Sutures not impressed or 

 otherwise specially marked. Surface, to ordinary vision, apparently 

 smooth, but a good lens shows it to be very finely granular. 



Height, 9 millimeters ; breadth, 7^ millimeters. 



Position and locality. — Upper Coal Measure strata, thirty miles west of 

 Humljoldt, Kansas. See introductory remarks. 



Genus Erisocrinus, Meek and Worthen. 



Erisocrinus planus (sp. nov.). Plate 1, figs. 6 aud 7. 



Body rather small, subcircular or obscurely pentahedral as viewed 

 from above or below, shallow convex-basin-shaped from the top of the 

 first radials downward ; base somewhat deeply impressed at the center, 

 the depression gradually rounding outwaril to the sides; basal pieces 

 very small, occupying the bottom of the depression of the base and al- 

 most covered by the first joint of the column ; subradial pieces mod- 

 erately large, their inner ends bent inwardly by the depression of the 

 base to meet the small basal pieces there, their outer ends extending 

 outward and upward so as to be more or less plainly visible by side 

 Anew of the body ; first radial pieces comparatively large, convex verti- 

 cally, their upper edges rounded inward to the suture between them aud 

 the second radials, their lower angles extending downward almost to 

 the lowest portion of tlie body visible by side view. The other charac- 

 ters are those common to the genus. One minute piece remains attached 

 to the upper border of the calyx of one of the specimens, at the junction 

 of two of the first radial pieces. This is no doubt an anal piece, its 

 outer surface being in the plane of the outer surface of the calyx, but 

 it does not in any degree enter betwe^^n the two first radials upon which 

 it rests. 



Transverse diameter of the calyx, 14 millimeters ; height of the same, 

 5 millimeters. 



Proc. Nat. Mus. 79 17 Jan. 27, 1 880.. 



