356 FOSSIL OSTKEID^ OF NORTH AMEEICA. 



PLATE XLV. 



OsTREA BLACKii White. (Page 292.) 



Fia. 1. — Upper view; uatural size. For another view see next plate. 



OsTUEA BARRANDEi Coquand. (Page 292.) 



2. — Interior view of the lower valve. For other views see Plates XLTV and 

 XLVI. 



OSTREA (AiECTRYONIA) 8ANNIONI8 White. (Page 300.) 



3,4,5. — Exterior view of three different valves; natural size. 

 6, 7. — Interior views of a right and left valve. 



