EXPLANATION OF PLATE 45 



Fig. 1. Pecten weaveri, n. sp. Left valve. A common species in the Lower 

 San Pablo of the type section. Longitude, 57 mm. Natural s±ze. 



Fig. 2. Pecten weaveri, n. sp. Eight valve. Natural size. 



Fig. 3. Pecten crassicardo Conrad. Bight valve. Common in both the Upper 

 and Lower San Pablo. Longitude, 150 mm. About two-thirds natural size. 



L520] 



