Some New Species of Fossils from the Cincinnati Group. 351 



little over half the breadth of each valve. Ventral and terminal mar- 

 gins bordered by a very narrow depressed rim. 



Length of specimen about xlij- ii^ch ; breadth about two thirds the 

 length. 



It is found associated with B. quadrilirata, on slabs, about three 

 miles east of Weisburg on the I. & C. R. R., and with the same fossil 

 and B. Chambersi, about two miles north-east of Fort Ancient, on the 

 L. M. R. R. The rocks at each of these places are about 300 feet be- 

 low the upper silurian. 



Leperditia cylindrica (Hall.) 



This species is distributed throughout the rocks of the Cincinnati 

 Group, and is quite variable in form and size. It was described from 

 cylindrical specimens, only about two hundredths of an inch in length ; 

 but forms five hundredths or six hundredths of an inch in length, and 

 having the anterior third much enlai'ged, making a club shaped shell, 

 by reason of the minute gradations from one extreme to the other, may 

 be classified with it. The largest and best club shaped specimens, 

 I found abundant, on rocks, in the run, on the O. & M. R. R., 1| 

 miles east of Laughery creek, or about 44 miles west of Cincinnati. 

 At first, I was disposed to treat this latter form as sufficiently distinct 

 to warrant me in naming it ; but after an examination of large num- 

 bers, I came to the conclusion, that I was unable to separate it, by any 

 constant characters. 



Beijrichia ciliata (Emmoijis.) 



This species, described by Prof. Emmons, in his American Geology, 

 from the Blue limestone of Ohio, I believe, is the same, that was de- 

 scribed, bv Prof. Hall, many years later, under the name of B. tumi' 

 from. Emmons figured the interior and Hall the exterior, but there 

 does not seem to be much difficulty, in determining the fossil, from 

 Emmons' figure and description, moreover, there is no other form, 

 known in the Blue limestone of this locality, that could for a moment 

 be confounded with it. 



Beyriehia regularis (Emmons.) 



This species was described by Prof. Emmons, in his American Geolo- 

 gy from the Blue limestome of Ohio, and though his figure is not very 

 good, I know of no form so closely related to it, as B. quahiUrata of 

 Hall'and AVhitfield, in the 2nd volume of Ohio Paleontology. The 

 latter name will be found, probably, to be a synonym. 



