THE SUBSPECIES OP FUR SEAL. 45 



THE ROBBEN ISLAND HERD. 



The third herd is resident in the Sea of Okhotsk on Kobben Island, where a 

 considerable reuinaut still exists, and formerly occupied other rookeries, now virtually 

 extinct, on four islands of the Kuril group Musir, Eaikoke, Sreduoi, and Broughtou. 

 The migration route of this herd lies in the inland sea of Japan. 



THREE DISTINCT SPECIES. 



The fact that the seals of the Pribilof herd differ from those of the Commander 

 Islands in color, in form, and in character of the fur has long been recognized. These 

 differences, though slight, are permanent and constant. As no intermediate forms 

 are known, and as the life courses of the herds are wholly distinct, apparently no 

 intermediate forms can exist. We may therefore hold that the herds represent 

 distinct species. As the Komandorski seals formed the type of Callorhinus ursinus, 

 the Pribilof seals may be taken to represent a new species, to which the name 

 . Callorhinus alascanus may be given, and the Bobben Island herd, likewise different, 

 may be called Callorhinus curilensis. 



CALLORHINUS ALASCANUS. 



The description of this new species or subspecies is given in full in a special paper 

 which appears in Part III. It may be noted here that alascanus may be known by the 

 stouter, broader head, by the thicker neck, by the prevalence of warm, brown shades 

 in the coloration of the females and the young males, by the more silvery color of the 

 gray pups, which have the whitish patches on the rump less than in ursinus. In 

 general it shows a lack of sharp contrast between the coloration of the sides and belly. 

 The fur is of superior quality and exhibits sufficient difference to make it possible for 

 the dealers handling the skins to distinguish them by this means alone. In alascanus 

 the claws on the foretiipper are undeveloped, being represented by pits in the skin. 



CALLORHINUS URSINUS. 



The true ursinus has a slenderer head and neck. The females and young males 

 are sooty rather than brown, the light and dark shades being alike for the most part 

 without ochraceous tints. The belly is usually rather sharply paler than the back, 

 and the gray pup is more brownish and less gray than in the Pribilof animal, having 

 a pale patch on each side of the rump. The fore feet have two or three rudimentary 

 claws. 



CALLORHINUS CURILENSIS. 



The seal of Kobben Island and the Kurils, differs from both of the foregoing in 

 the whitish color of the under fur. This is rusty brown in ursinus and alascanus. It 

 is said also to have a broader head than ursinus and to exhibit other differences in 

 the quality of the fur, distinguishing the seals of Kobben Island from either of the 

 other herds. 



In the following discussion our attention will be directed chiefly to a consideration 

 of the Pribilof Islands seals. In Part IV of this report the herds of the Kouiaudorski 

 and Kuril islands will be discussed in detail. 



