Brcxldopoda of the Cincinnati Grouj). V^ 



Crania Dyerl — (S. A. INIilleu). 



Fig. 3. — Crania Di/eri. 



Shell small, circular ; dorsal valve prominent, conical ; apex cen- 

 tral. Surface marked by six or seven fine, sharply elevated, concen- 

 tric ridges or laniellose lines of growth. Ventral valve and interior 

 unknown. 



Diameter of specimen, 0.20 inch ; convexity, 0.07 inch. 



Found within 250 feet of Ioav water-mark, at Cincinnati. Extremely 

 rare. 



The specimen figured is from the magnificent collection of C. B, 

 Dyer, Esq.. in whose honor I have given the specific name. 



Crania multrpundata — (S. A. Miller). 



Fig. 4. — Crania muliipvnctafa. 



Shell small, subrectangular or irregular in outline ; dorsal valve 

 moderately prominent ; apex subcentral or about one third the length 

 of the valve from the cardinal margin. 



Surface marked by numerous fine punctures, just visilile to the naked 

 eye, but giving the shell a highly ornamental appearance under an 

 ordinary magnifier. Ventral valve and interior unknown. 



Length of specimen, 0.32 inch; width, 0.24 inch; convexity, 0.07 

 inch. 



The specimen figured I found near the upper part of the hills in 

 Cincinnati. Mr. C. B. Dyer has a specimen, collected in the same 

 range, and it is so in the collection of U. P. James, Esq. 



Genus PhoUdojos — (Hall, 1859). 



Shells small, patelliform; apex subcentral, eccentric or terminal. 

 Surface marked by concentric lamella; of growth, which are more ex- 

 panded on the posterior side. Interior a shallow oval cavity, with 

 bilobed muscular impressions ; the margin flattened or slightly deflect- 

 ed and entire. 



