Braclilopoda of the Cincinnati Gronjp. 61 



or a little anterior; mesial ridge prominent as it approaches the middle 

 and anterior parts, and consisting of four simple, angular, radiating 

 costae ; lateral slopes each occupied by six similar costse, regularly slop- 

 ing to the margins ; beak closely incurved beneath the beak of the 

 ventral valve. 



Ventral valve moderately convex ; mesial sinus not quite reaching 

 the beak, but deep and well defined in the middle and anterior 

 regions, and containing three simple, angular, radiating costse ; lateral 

 slopes each occupied by six similar costse gradually curving to the 

 margins ; beak prominent, perforated (?) and slightly incurved upon 

 that of the dorsal valve. 



Fig. 6.— Front view. Fig. 7.— Dorsal view. 



Surface of both valves marked bv distinct lines of growth crossing 

 the plications. Sometimes the mesial ridge of the dorsal valve in old 

 specimens becomes so prominent as to be humped anterioi'ly. Interior 

 unknown. 



Length of specimens collected varymg, from 0.34 to 0.66 inch; 

 breadth, from 0.32 to 0.74 inch; convexity, from 0.18 to 0.48 inch. 



I collected this species in the railroad cut at Paris, Kentucky, but do 

 not know the exact position of the rocks in the Cincinnati Group. I 

 suppose them to be somewhere in the upper part. It may be that 

 this species should be classed in the genus Ehynchonella. 



Trematoqyira (f) granulifera — (Meek, 1872). 



Shell transversely oval, length about four fifths the breadth, moder- 

 ately convex, convexity of the two valves being nearly equal; lateral 

 margins rather narrowly rounded in outline ; front and anterior lateral 

 margins broadly rounded, or perhaj)s the former sometimes straight 

 or slightly sinuous in outline in the middle ; cardinal margin nearly 

 straight on each side, and sloping at an angle of about 140° from the 

 beaks toward the lateral extremities. 



Dorsal valve nearly evenly convex, its greatest prominence being 

 sliglitly behind the middle, provided with about tliirteen simple, 

 angular, radiating plications, five of which on the middle are smaller 



