PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 259 



which are adjacent to the anal series being very little if any narrower 

 than the others : arm facets large, about one-third wider than high, 

 their plane being nearly vertical, notched at the upper border and 

 marked transversely by the double ridge or raised lines which are com- 

 mon to the arm facets of many of the Gyathocrinidw; anal pieces three 

 known, nearly equal in size, or the first a little larger than the two second, 

 each with a i^rominent tubercle at the center ; first anal piece five-sided, 

 abutting against one subradial, two first radials and two second anal 

 pieces ; the two second anal pieces abut against the first anal, against 

 each other, and each abuts against a first radial. 



Diameter of calyx, 14 millimeters; height of the same, 6 millimeters. 



This is the first and only species of true Gyathocrinus that has to my 

 knowledge yet been discovered in Upper Coal Measure strata ; G. in- 

 flexus^ Geinitz, and G. hemisphericus, Shumard, sp., not being regarded as 

 typical species of that genus. It belongs to a tyi)e that is more char- 

 acteristic of the Burlington limestone division of the Subcarboniferous 

 than of any other division of the great Carboniferous series, and to- 

 gether with the next described form it shows the crinoidal fauna of the 

 Upper Coal IVIeasures to be more intimately related to that of the Sub- 

 carboniferous than it has before been known to be. 



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

 of Humboldt, Kansas. See introductory remarks. 



Genus Rhodocrinus, Miller. 



Rhodocrinus vesperalis (sp. nov.). Plate 1, figs. 11 and 12. 



Body subglobose, the sides and outer portion of the base continuously 

 convex ; the base having a deep, sharply defined, five-sided pit which 

 contains the whole of the five basal pieces, and also the sharj)ly in- 

 flexed inner ends of the five subradial j)ieces ; the latter pieces moder- 

 ately large, but not much larger than some of the radials and inter- 

 radials ; first radial pieces varying a little in size in the different rays, 

 the larger ones nearly or quite as large as the subradial ; second radials 

 much smaller than the first, and the third radials still much smaller 

 than the second, the difference in size being greater in their vertical 

 than in their transverse diameter. The third radial in each ray, which 

 is very narrow vertically, supports two brachial pieces, and they in turn 

 each support anotlier brachial piece, beyond which the structure is un- 

 known ; interradial pieces up to a line with the center of the arm bases, 

 three for four of the interradial spaces, and four for that of the anal 

 side; the first or lower interradials are of about equal size in each of 

 the spaces, and a little larger than the two next aboA'^e ; dome moder- 

 ately convex, prominent opposite the arms and somewhat depressed be- 

 tween them, composed of numerous small pieces ; proboscis subcentral, 

 its length unknown. All the pieces of the body, except those of the 



