200 Cincinnati Society of Natural Fiistory. 
produced in the antero-ventral and postero-dorsal regions; umbili- 
cal pit oval, sharply defined, situated a little in front of the center ; 
margins smooth, thickened on the inner side where they overlap 
the edges of the smaller left valve except at the straightened dorsal 
side. Left valve nearly egg-shaped, narrowing anteriorly, with 
the umbilical pit situated higher than on the opposite valve. Sur- 
face of both valves with strong, more or less flexuous longitudinal 
striae. 
This species resembles B. punctostriata in many respects, but is 
distinguished by being shorter, smaller, and more convex, and in 
having slightly coarser striz, no puncte between them, and the 
umbilical pit more centrally situated, and of rounded form. 
Position and locality: Devonian Bryozoa bed, Falls of the Ohio. 

Jeeves JEL be 
CARBONIFEROUS SPECIES. 
LEPERDITIA NICKLESI, Nn. sp. 
Elate, X VITLS Pies. AVON GKane 
Size: Length, 1.15 mm.; height, 0.77 mm.; thickness (of left 
valve), 0.25 mm. 
Valves small, oval, widest posteriorly; hinge line short, straight ; 
surface almost uniformly convex, often with obscure pimples espe- 
cially in the posterior half. Eye tubercle represented by a spine- 
like prominence near the antero-dorsai angle. 
The spine distinguishes this species from ZL. carbonaria, (Hall). 
In L. armstrongiana, Jones and Kirkby, the spine is larger and 
farther removed from the dorsal edge. ‘The latter is longer, and 
the outline on the whole much less exactly egg-shaped. 
Named for Prof. J. M. Nickles, of Sparta, Ill., who was my 
companion on the trip that resulted in the discovery of this and 
other interesting species. 
Position and locality: Warsaw beds of the St. Louis group, 
Columbia, Monroe Co., Ill. 
