trast between the compressed posterior and the inflated anterior 

 ends. These differences, however, may be due to the fact that the 

 Sharon specimens occur as internal casts, while the shell is preserved 

 on the Morrow forms. 



Horizon and locality. Sharon ore: Lick Run, Scioto County 

 (Locality 2), c. 



Genus Anthraconeilo Girty 



Anthraconeilo bownockeri n. sp. 

 PL IV, Fig. 21 



Description. Shell small to almost medium in size, transversely 

 ovate in outline, ratio of height to length about 2 : 3, maximum height 

 about one- third the length of the shell from the posterior margin; 

 moderately convex in umbonal region, becoming compressed anter- 

 iorly and slightly so at the posterior margin; beak directed posteriorly, 

 prominent, elevated above hinge line and slightly incurved, situated 

 about one-third the length of the shell from the posterior margin; 

 anterior-dorsal margin long, sloping downwards from the beak to the 

 anterior extremity which is bluntly pointed and considerably produced ; 

 posterior margin broadly rounded; ventral margin rounded sloping 

 strongly upward anteriorly to meet the pointed anterior extremity. 

 Surface of internal cast smooth. 



Dimensions. The measurement of the holotype are: length 

 18 mm., height 11 mm., convexity of left valve 3.5 mm. 



Remarks. This species of Anthraconeilo is of rare occurrence 

 and has been found only in the Sharon ore from which internal casts 

 of single valves of only three individuals have been discovered. It 

 differs from A. taffiana Girty principally in its smaller size and its 

 more pointed anterior extremity, which in the latter species is blunt 

 and somewhat truncated. It is closely similar to A.kessleriana 

 (Mather), but may be distinguished by its less centrally located 

 beaks and its more produced anterior end (the long pointed one), 

 which give to the shell a decidedly more transversely-elongate form. 



Horizon and locality. Sharon ore: Lick Run, Scioto County 

 (Locality 2), r. The specific name is given in honor of Dr. J. A. 

 Bownocker, State Geologist of Ohio. 



Genus Parallelodon Meek 



Four species of Parallelodon are among the collections of Potts- 

 ville fauna studied: P.carbonarius, P.obsoletus, P.sangamonensis, 

 and P.tenuistriatus, all of which are abundant except P. sangomonensis. 

 The genus extends from the Harrison ore at the base throughout 

 the entire formation but occurs most abundantly in the Lower Mercer 

 and McArthur members. 



Parallelodon carbonarius (Cox) 



1857 Area carbonaria. Cox, Geol. Surv. Ky., Vol. 3, p. 567, PL 8, Fig. 5. 

 Coal Measures: Kentucky. 



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