NEOCENE STRATIGRAPHY. 339 



A better knowledge of both the fossil and living fauna 

 would unquestionably modify these results, but it is be- 

 lieved that it would not materially alter them. Had all 

 the species collected been identified it is thought the per- 

 centages given would be somewhat lower. 



The field work done by the writer in Los Angeles 

 county has shown that the Coast Ranges are not all of 

 one age. The Santa Cruz Mountains were certainly 

 elavated at a later date than the mountains of Los Angeles 

 county. The suggestion is made that the parallel ranges 

 ■of the Central California coast line agree in age with the 

 Santa Cruz Mountains; that the east and west ranges of 

 Santa Barbara county, and to the south, are of one age, 

 having beeui raised during the Merced Period and near 

 the close of the Miocene, Attention has been called 

 above to the presence at San Fernando of fossiliferous 

 strata conformably above the Monterey series. The 

 fauna of these strata has also been shown to agree closely 

 in its character with the fossiliferous or transitional beds 

 at the bottom of the Merced series. The mountains of 

 that region were evidently raised soon after and before the 

 deposition of the uppermost beds of the Merced series 

 in the Santa Cruz Mountains. This is shown by the ex- 

 istence at San Pedro and elsewhere along the coast of 

 horizontal strata, evidently of later age than the neighbor- 

 ing mountains, which contain an abundant fauna, believed 

 to correspond with the fauna of the top of the Merced 

 .series in the Santa Cruz Mountains. 



THE PLIOCENE OF SAN PEDRO. 



The plain of Los Angeles, stretching from the city to 

 the coast, is broken at the harbor of San Pedro by a long 

 hill, 1475 feet high, according to the Coast Survey, known 

 as San Pedro Hill. It is smooth and bare of timber, but 

 interesting, both on account of its terraces, of which 



