DESCRIPTION OF SPECIES ' 



PHYLUM ECHINODERMATA 



Class Crinoidea 

 Genus Eupachycrinus Meek and Worthen 



Eupachycrinus mooresi (Whitfield) 

 PI. Ill, Figs, l, 2 



1882 Zeacrinus mooresi. Whitfield, Ann. N. Y. Acad. Sci, Vol. 2, p. 227. 



Coal Measures: Carbon Hill, Hocking Co., Ohio. 

 1895 Zeacrinus mooresi. Whitfield, Geol. Surv. Ohio, Vol. VII, p. 483, PL 11, 



Figs. 6-10. 



Coal Measures: Carbon Hill, Hocking Co., Ohio. 



Description. Spines of a crinoid closely resembling those des- 

 cribed by Whitfield on the second radial plates of Z. mooresi are not 

 uncommon in the members of the Pottsville formation above and in- 

 cluding the Boggs limestone. Whitfield's description of these spines, 

 which were obtained from Carbon Hill, Hocking County, is quoted 

 below: 2 



"The second radial plates present the strong specific feature of 

 the species, and are large and spine-bearing, as in Zeacrinus mucro- 

 spinus McChesney. The spines are long, much thickened, and bul- 

 bous in the lower part, presenting in this respect a strong contrast 

 with those of that species. The cicatrix for the attachment of the 

 arm plates is very large, showing that the plates above were of large 

 size 



The species has been quite abundant, as the spines are found 

 in great numbers, and vary considerably in size, according to the 

 width of the first radial plates upon which they have rested. But 

 all are thickened and bulbous, and many of them are more than an 

 inch in length. They are seldom found attached to the calyx, but 

 are scattered through the shale in the bed where found." 



At no locality in the Pottsville formation from which collections 

 were made for the present report, are these spines found as abundantly 

 as at Carbon Hill. 3 The close resemblance of the spines in question 

 to those described above, combined with stratigraphic and geographic 

 evidence, points to identification with the Carbon Hill species, although 

 no other portions of the calyx have been discovered. The figured 

 specimen of a calyx of E. mooresi from carbon Hill is included to 

 show the attachment of the second radial plates and spines to the 

 first radial plates. 



>In the descriptions of the Pottsville species the following symbols are used: aa, very abundant: 

 a, abundant; c, common; r, rare. 



sWhitfield, R. T., Geol. Surv. Ohio, Vol. VII, p. 483, 1893. 



3 The exact stratigraphic position of the horizon from which the Carbon Hill fauna described by 

 Whitfield came, cannot be stated definitely at present, although it is known to be either upper Pottsville 

 (probably McArthur) or basal Allegheny. After the completion of additional field work, the Carbon 

 Hill fauna will be described in a separate paper, a portion of which is now in manuscript. 



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