49 



This species is distinguished by its depressed form, peculiar, 

 sculptured ornamentation, three arms to each radial series, and 

 forty ovarian apertures The slightest observation will enable 

 any one to distinguish it from all other fifteen-armed species. 



Found by Geo. K. Greene in the Hamilton Group, near 

 Charlestown, Indiana, and now in the collection of Win. P. E. 

 Gurley. 



Family CYATHOCRINID-K. 



CYATHOCRINUS WALDRONENSIS, Miller & Dyer. 



Plate III, Fig. 19, azygous view; Fig. 20, opposite vieiv. The 



specimen is compressed laterally, and magnified 



two diameters. 



This specimen was described, in l*7. s , in "Contributions to 

 Pakeontology No. 2," page (i. from a specimen that did not 

 show the interradials or azygous plates, and which was poorly 

 illustrated on plate IV. Fig. 9, from a specimen then owned 

 by the late C. B. Dyer. The species is extremely rare and we 

 are glad to be able to refigure it, from a better specimen than 

 the original, though it is the second specimen we have ever 

 had the opportunity to examine. 



Calyx forms a cup one half wider than the height, and hav- 

 ing the basals sunk within the cavity of the calyx. Surface 

 granular. Column small and round. 



Subradials of unequal size, longer than wide and curving 

 into the small columnar cavity where they abut upon the basals. 

 The azygous one is larger than either of the others. The first 

 primary radials are larger than the subradials and about twice 

 as w 7 ide as long. The second primary radials are very short 

 and quadrangular. The third primary i-adials are about the 

 size of the second, pentagonal, axillary and support upon the 

 upper sloping sides the free arms. There are, therefore, ten 

 arms, in this species. Above the first two plates the arms are 

 composed of a double series of interlocking plates. The arms 

 are coarse, wide, and short. 



A single interradial, in each area, curves in upon the vault. 

 The azygous plate is longer than wide, truncates a subradial, 

 stands nearly vertical and extends as high as the third primary 

 radial. 



The specimen here illustrated and described was found in 

 the Niagara Group near Hartsville, Indiana, by Dr. M. N. 

 Elrod and is now in the collection of Win. F. E. Gurley. 

 — 7 



