In his study of the fauna of Flint Ridge, Herrick l mentions that 

 possibly two related species differing chiefly in size may exist; in the 

 writer's opinion if the characters exhibited in his figure prove constant 

 in a number of specimens, a different species rather than an abnormal 

 development of P.tropidophorus is represented. This form differs 

 not only in its larger size, but in its less angular posterior outline and 

 its convex ventral margin. Collections were made at a number of 

 localities along Flint Ridge, but no specimens comparable to Herrick's 

 were discovered. 



Horizon and locality. Lowellville member: Poverty Run, Mus- 

 kingum County (Locality 19), r. Common in the Lower Mercer 

 and upper Pottsville members. 



Pleurophorus oblongus Meek 



1866 Clidophorus pallasi. Geinitz, Garb, und Dyas in Nebr., p. 23, tab. 2, Fig. 4. 



(Not Modiola pallasi de Vern., 1845.) 



Nebraska City and Wyoming, Nebraska. 

 1872 Pleurophorus oblongus. Meek, U. S. Geol. Surv. Nebr., p. 212, PI. 10, Figs. 4a-c. 



Upper Coal Measures: Nebraska City, Nebraska. 



Represented in the lower Pottsville formation by the internal 

 cast of a single specimen from the Sharon ore, which, however, is in 

 an almost perfect state of preservation so that the identification is 

 made with a considerable degree of confidence. This specimen is 

 somewhat smaller than indicated by Meek's description and figures; 

 its dimensions are: length 8 mm., length of hinge line 6 mm., maximum 

 height near posterior end 4.5 mm., thickness of right valve 1.2 mm. 



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

 (Locality 2), r. Also present in the Lower Mercer limestone. 



Genus Astartella Hall 

 Astartella concentrica (Conrad)? 



1842 Nuculites concentricus. Conrad, Acad. Nat. Sci. Philadelphia Jour., 1st Ser., 



Vol. 8, Pt. 2, p. 248. 



Coal Measures: Pennsylvania. 

 1913 Astartella concentrica. Girty, U. S. Geol. Surv., Bull. 544, p. 142, PL XVIII, 



Figs. 2-9. 



Wewoka formation : Oklahoma. 



Several small, imperfect specimens belonging to the genus Astar- 

 tella have been referred to this species. The poorly-preserved condi- 

 tion of the material, however, renders the identification doubtful. 



Horizon and locality. Lowellville member: Poverty Run, Mus- 

 kingum County (Locality 19), r. Boggs limestone: near Hopewell 

 P.O., Muskingum County (Locality 26), r. 



Astartella sp. 



A small, crushed pelecypod, probably belonging to the genus 

 Astartella, occurs in great abundance at two localities, one in the 



iHerrick, C. L., Bull. Den. Univ., Vol. II, p. 35, 1887. 



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