1922 J Kellogg: Pinnipeds from Miocene and Pleistocene Deposits 51 



on his return to London published a report concerning his geological 

 explorations on Martha's Vineyard, Massachusetts, and mentions the 

 finding of a skull of a fossil walrus, presumably in the Pleistocene 

 deposits, which differed from the skulls of existing species in having 

 six molars (i.e., three pairs) and two tusks. After some years had 

 elapsed, another strongly silicified skull was found at Long Branch, 

 Monmouth County, New Jersey. This find was reported upon by 

 Leidy. 39 Again in 1878, Cope 40 reported a fossil walrus skull with 

 tusks over five inches long from the Quaternary blue clays of Port- 

 land, Maine. Previous to this, Leidy 41 had given an account of the 

 discovery of a fossil walrus tusk in the Ashley phosphate beds of South 

 Carolina. More recently Rhoads 42 mentioned the finding of a fossil 

 walrus skull on Sable Island, Nova Scotia. The last specimen to be 

 found is the skull from Kitty Hawk Branch, North Carolina, which 

 was discussed by Hay 43 at a meeting of the Biological Society of 

 Washington. 



The birthplace of the early ancestors of the Odobenidae cannot 

 as yet be definitely decided, though the evidence points to the fact 

 that they had their origin in the Holarctic region, possibly in the North 

 Pacific Ocean. Prom a study of the past and present distribution 

 of this family, it seems probable that they had their origin in the 

 North Pacific and that during Oligocene time they migrated to the 

 Atlantic by way of the sea which then separated North and South 

 America. A possible criticism of this interpretation would be the fact 

 that fossil Odobenidae are unknown from the Pacific Coast, but this 

 is only negative evidence since explorations of marine beds in a search 

 for vertebrates have scarcely begun. An alternative interpretation 

 would be that the walruses had their origin in the North Atlantic and 

 that the present North Pacific forms represent a comparatively recent 

 invasion by way of the Arctic Ocean. 



There seems to be no alternative interpretation if we are to derive 

 the walruses from the eared seals, as we must according to our present 

 evidence. It is well known that in the Recent period the Otariidae 

 have been limited almost exclusively to the Pacific Ocean, though 



39 Leidy, J., Notice of remains of the walrus discovered on the coast of the 

 United States. Trans. Am. Philos. Soc, vol. 11, pp. 83-86, pi. 4, figs. 1-2, pi. 5, 

 fig. 1. Philadelphia, 18(30. 



« Cope, E. D., Fossil walrus. Am. Nat,, vol. 12, p. 633. 1878. 



4i Leidy, J., Am. Jour. Sci. (3), vol. 12, p, 222. 1876. 



42Ehoads, S. N., Proc. Acad. Nat. Sci. Phila., vol. 50, p. 201. 1898. 



43 Hay, O. P., Proc. Biol. Soc. "Washington, vol. 28, p. xiii. 1915. Jour. Wash- 

 ington Acad. Sci., vol. 6, p. 78. 1916. 



