1902.] Allen, North Pacific Phocida. 47 * 



COMPARISON OF THE ATLANTIC AND PACIFIC FORMS OF THE 

 PHOCA VITULINA GROUP. 



The skulls of the Phoca vitulina group available for study 

 from the coasts of the North Pacific and Bering Sea number 

 26. They include i from Santa Barbara Islands; 2 from 

 Puget Sound; i from Yakut at Bay; i from Kenai, Alaska; 

 i from Adakh Island, Aleutian Islands; 4 from St. Michaels. 

 To these may be added 4 from Point Barrow; 3 from the 

 Pribilof Islands; 4 from Bering Island; 2 from Avatcha Bay, 

 Kamschatka ; 5 from mouth of Gichiga River, Okhotsk Sea. 

 The Point Barrow, Kamschatkan, and Okhotsk specimens, 

 however, represent species quite distinct from those from the 

 Pacific coast of North "America. Hence the really available 

 material for comparison with the Atlantic coast specimens 

 consists of the skulls from the Pribilof Islands and St. 

 Michaels, Alaska, and a few from more southern points on 

 the Pacific coast. These are nearly all young, and not one 

 is identified as to sex. The general appearance of the St. 

 Michaels skulls seems to indicate that three of them are females 

 and the other a male. These and the other Pacific coast 

 skulls, compared with Atlantic coast skulls of closely corre- 

 sponding ages, show the following resemblances and differences. 



Cranial Differences. In the Pacific coast skulls the pre- 

 maxillas ascend not only to the nasals but extend posteriorly 

 so as to touch the sides of the nasals for about 8 to 10 mm. ; 

 in the Atlantic coast specimens the premaxillae barely touch 

 the nasals (in some cases do not quite reach them) a distinc- 

 tion, according to Dr. True, first made known by Dr. Merriam. 1 

 This distinction appears to be constant in all the skulls I have 

 examined from the Alaskan and Kamschatkan coasts, as com- 

 pared with those of the Atlantic coast. 



Dental Characters. A careful comparison of the Alaska 

 and Puget Sound skulls, tooth by tooth, with 'the Atlantic 

 coast specimens, reveals no tangible differences between the 



1 Cf. True, in Jordan's 'Report on the Fur Seals and Fur-Seal Islands of the North 

 Pacific Ocean,' Part III, 1899, p. 351. At a meeting of the Biological Society of Wash- 

 ington, held Jan. 30, 1897, Dr. Merriam is recorded (Proc. Biol. Soc. Wash. XI, 1897, 

 p. viii) as having presented a communication on 'The Pribilof Island Hair Seal,' but the 

 paper does not appear to have been published. 



