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University of California Publications in Geology [Vol. 13 



PAGE 



Middle Pliocene (Sealdisian) 



Upper Pliocene (Astian) 



Pleistocene 



Phocinae 



Monachinae 



Lobodoninae 



75 

 75 

 78 

 81 

 87 

 89 

 90 

 92 

 97 

 101 



Cystophorinae 



Paleontologic evidence bearing on the origin of the pinnipedia 



Conclusions 



A check list of fossil pinnipedia 



INTRODUCTION 



Although in paleontologic studies considerable information relating 

 to marine invertebrates and land vertebrates of the Pacific Coast 

 province has become available within the past few years, it is surpris- 

 ing how meager our knowledge remains regarding the fossil pinniped 

 forms. The problems which members of this group present cannot 

 be said to lack interest for the evolutionist, for much remains yet 

 to be discovered concerning the derivation, descent, and adaptation 

 of the marine carnivorous mammals. Nor does the present dearth 

 of fossil pinniped material seem entirely warranted in the light of 

 the extensive explorations for, and study of, the marine Pleistocene 

 and, particularly, the Tertiary fauna of the west coast. While the 

 preservation of remains of seals and allied forms may not have been 

 so favorable, because of their mode of life, as that of invertebrate 

 faunas, systematic search in marine deposits ought to reveal much 

 valuable material. This seems an assured fact, considering the com- 

 pleteness of the Tertiary and Pleistocene marine sections, and the 

 great geographic extent of the deposits. 



The present study deals with small collections of pinniped remains 

 that have been assembled in the Department of Paleontology, Univer- 

 sity of California, in the California Academy of Sciences and by the 

 Geological Department of the Southern Pacific Railway Company. 

 In a review of this material it became evident to the writer that 

 obstacles making the problem of the pinnipeds difficult of approach 

 were in a measure owing to the scattered nature of the literature and 

 to confusion arising from the description and inaccurate determina- 

 tion of fragmentary material. A check list has therefore been added 

 to facilitate future reference. 



