iMemdirsCal Acad. Sci.Ydl III. 



[Arnold] Piatc XXV^II 



Figure a. San Pedro.— North end of the San Pedro bluff, looking northwest, showing fossiliferous 

 layers near top. Photograph by R. Arnold. 



Figure b. San Pearo.— North end of the San Pedro bluff, looking southwest, showing fossiliferous 

 layers at the bottom. Photograph by R. Arnold. 



