118 DELOS AND RALPH ARNOLD 
California, which extends from Point Concepcion on the north 
to San Diego on the south. A few references have been made 
by previous writers to the marine Pleistocene geology of western 
North America, but the inadequacy of their observations has 
failed to give a proper conception of the importance of the 
Pleistocene as developed along the southern California coast. 
SantaRosa 
SKETCH MAP 
of the 
COAST 
SOUTHERN, CALIFORNIA 
Rady Agnola San Clemente 
| 
° 10 20 
30 40 soMiles t 
The field work upon which this paper is based has extended 
over a period of several years, during which time the writers 
have made a detailed study of the paleontology and stratigraphy 
of the Pleistocene and subjacent formations at San Pedro,’ and 
have also visited and studied the formations at most of the locali- 
ties from San Francisco to San Diego at which Pleistocene 
sediments are exposed. The deposits at San Pedro, being the 
best developed and most easily accessible, have been taken as 
the type series. 
« The junior author has in press as a memoir of the California Academy of Sci- 
ences a paper entitled “The Paleontology and Stratigraphy of the Marine Pliocene 
and Pleistocene of San Pedro, with Notes on Similar Formations of the Adjacent 
California Coast.” 
