200 POTTSVILLE FAUNA OP OHIO 



Dimensions. A specimen of average size measures: length 15 mm., 

 height at beaks 8.5 mm., convexity of right valve 2 mm. 



Horizon and locality. Lower Mercer limestone : Muskingum 

 County, Locality 43, r; Licking County, Locality 47, c. McArthur 

 member: Jackeon County, Locality 80, c; Vinton County, Locality 84, c. 



Edmondia ? peroblonga Meek and Worthen? 



1865 Edmondia ? peroblonga. Meek and Worthen, Proc. Acad. Nat. Sci. Phil., p. 249. 



Upper Coal Measures: LaSalle, Illinois. 



1873 Edmondia ? peroblonga. Meek and Worthen, Geol. Surv. 111., Vol. 5, p. 583, 

 PI. 27, Fig. 4. 

 Upper Coal Measures: LaSalle, Illinois. 



Remarks. A form closely related to Edmondia ? peroblonga occurs 

 in the Boggs limestone of Muskingum County; it is represented by a 

 single specimen somewhat imperfect at the posterior extremity. The 

 size is about two-thirds that of the specimen described and figured by 

 Meek and Worthen, although the resemblance between the two forms 

 is so close, that they represent in all probability the same species. How- 

 ever, as E. ? peroblonga occurs much higher in the Pennsylvanian system, 

 and as the Boggs specimen is imperfect, identification of the Ohio form 

 with this species is not at all conclusive. 



Dimensions. The measurements of the Boggs specimen are: 

 length 43 + mm., height 20 mm., convexity of the right valve 5 mm. 



Horizon and locality. Boggs limestone : Muskingum County, 

 Locality 26, r. 



Edmondia sp. 



Remarks. Specimens belonging to the genus Edmondia occur in 

 the Lowellville and Boggs members, but are too crushed and imperfect 

 to permit specific identification. 



Horizon and locality. Lowellville limestone: Muskingum County, 

 Locality 19, r. Boggs limestone: Muskingum County, Localities 26, 

 27, r. 



Genus Nucula Lamarck 

 Nucula beyrichi von Schauroth 



1866 Nucula beyrichi. Geinitz, Die Carb. und Dyas in Nebr., p. 21, Tab. 1, Figs. 36, 37. 



Nebraska City, Nebraska. 



Remarks. This species of Nucula is rare in rocks of Pottsville age 

 jn Ohio and is represented in the collections studied by only a few in- 



