Clark: The San Lorenzo Series of Middle California 101 



OTHER LOCALITIES 



There are several other general localities in the Coast Ranges, 

 where beds of San Lorenzo age are believed to be present, as indicated 

 by collections which the writer has seen. Beds of this period of 

 deposition are found along the east side of the Salinas Valley, south- 

 ern Monterey County, lying directly on the Franciscan (Jurassic) 

 and underlying beds of Lower Miocene age. These beds in this area 

 have been generally mapped , with those of the Lower Miocene. No 

 one has yet studied this section with the idea that these lower beds 

 might be Oligocene ; thus in this locality, it remains for future work 

 to determine the stratigraphic relationship of the Oligocene beds with 

 those of the Lower Miocene. 



Another area, in which the writer believes that beds of San Lorenzo 

 age are probably present, is in the Santa Lucia Mountains in southern 

 Monterey County and to the north of Mount Santa Lucia, also south- 

 ern Monterey County. In the latter locality they are found uncon- 

 formably below the type section of the Vaqueros formation, Lower 

 Miocene. 



Correlation 



RELATION OF FAUNA OF SAN LORENZO SERIES OF THE REGION OF 

 MOUNT DIABLO TO THAT OF THE SAN LORENZO FORMATION 

 OF THE SANTA CRUZ MOUNTAINS 



The number of species common to the faunas of the San Lorenzo 

 series of the Mount Diablo region and the San Lorenzo formation 

 of the Santa Cruz Mountains shows conclusively that both belong 

 to the same general period of deposition. Several species are found 

 in the San Lorenzo of the type section which have not been found 

 in the region of Mount Diablo ; this is probably the result of different 

 environment rather than of difference in age ; apparent^ the San 

 Lorenzo beds in the Santa Cruz Mountains, for the most part, were 

 deposited in deeper water than those of the Mount Diablo region. 



The following species 72 are common to the San Lorenzo of the type 



section and to the San Lorenzo beds of the vicinity of Mount Diablo: 



Cardium lorenzanum (Arnold) Fusinus hecoxi (Arnold) 



Malletia packardi, n. sp. Natica (Ampullina) gabbi, n. sp. 



Solen gravidus, n. sp. Sinum seopulosum (Conrad) 



Tellina lorenzanum Arnold Solarium lorenzoensis (Arnold) 



Agasoma gravidum (Gabb) Turris periasolaxoides (Arnold) 



Fusinus (Exilia) lincolnensis Dentalium conradi Dall 



(Weaver) Dentalium radiolineatum, n. sp. 



72 The determinations, as given above, were made by the writer from collections 

 obtained at the type locality of the San Lorenzo. 



