1911] Swarth: Alaska Expedition of 1909. 141 



Ursus americanus pugnax, new subspecies. Island Black Bear. 



Type.— Adult male ; no. 8332, Univ. Calif. Mus. Vert. Zool. : 

 Eocky Bay, Dall Island, Alaska ; May 31, 1909 ; collected by A. 

 Hasselborg; orig. no. 15. 



Characters. — Differs cranially from Ursus americanus amer- 

 icanus from the adjacent mainland ; skull broad and heavy, with 

 the frontal bones conspicuously flattened. (See plate 6, figures 1 

 and 2.) 



Eemarks. — The island bear exhibit certain cranial peculiar- 

 ities which seem to justify their separation as an insular race. 

 They are certainly widely different from black bear taken at 

 other Alaskan points, Kenai Peninsula, Takutat Bay, and Taku 

 Inlet. Compared with skulls from these localities, as well as 

 with others from California and Oregon, the island specimens 

 present a very different profile. The frontal bones are flattened 

 and the sagittal crest raised, so that the highest part of the 

 cranium lies very far back, about at the fronto-parietal suture 

 rather than over the orbits, as in typical americanus. The post- 

 orbital processes are largely developed and raised, being in one 

 case actually higher than the intervening frontal region. The 

 temporal ridges are conspicuous, and the zygomata heavily built 

 and wide spreading, producing a relatively very broad skull. 

 In three examples (nos. 8332, 8333, 8326) the zygomatic breadth 

 is actually, as well as proportionately, greater than in any other 

 specimens of black bear at hand, or than any published measure- 

 ments I have seen. In general appearance these island skulls 

 are short and broad, heavily built and conspicuously ridged. 

 The larger ones bear a striking gener.al resemblance to a grizzly 

 skull from the interior of Alaska. 



Their conspicuous feature is the flat depressed forehead. 

 Vrsus a. carlottae from the Queen Charlotte Islands has the 

 cranium less arched than in americanus, but has an elongated 

 skull, whereas in these it is short and broad. Ursus americanus 

 kenaiensis (not Ursus kenaiensis Merriam, 1902) from the Kenai 

 Peninsula has a long narrow skull (see Allen, 1910, p. 6) .^ Skulls 



1 Since the above was written Dr. Allen has proposed the name Ursus 

 americanus perniger to replace his U. a. Tcenaiensis preoccupied. (See 

 "Errata," Bull. Am. Mus. Nat. Hist., vol. xxviii, April, 1910, D- 115.) 



