32 NORTH AMERICAN FAUNA. [no. 19. 



to rocky, mountainous parts of the Hudsonian zone, and consequently 

 we did not meet with it during the latter part of our trip, and only 

 heard of it through reports from the mountains at the headwaters of 

 the White and Tanana rivers. As elsewhere, it is familiarly known 

 as the 'whistler,' although occasionally rather inappropriately called 

 'ground hog.' Its long drawn whistle is peculiarly mournful, par- 

 ticularly when it breaks the deathly silence of some rock}^ canyon. It 

 loves to stretch at full length on top of a large rock and bask in the 

 sun. I frequently found it quietly enjoying itself in this manner. 



Castor canadensis Kuhl. American Beaver. 



It hardly seems possible that half a million or more beaver skin.'j 

 have been secured in the Territory of Alaska. The animal is now 

 almost as rare there as it is in the United States, the inevitable result 

 of continued pursuit by both whites and natives, which has so many 

 parallels that it is useless to emphasize it here. At Fort Selkirk I 

 saw several beaver skins taken on a small tributary of Stewart River, 

 and at St. Michael I found a very few in the warehouses of the trad- 

 ing companies. Beyond this I saw or heard nothing of them, 



Mus decumanus Pallas. Norway Rat. 



Large rats are exceedingly abundant at St. Michael. Their intro- 

 duction must have been effected very recently, as they were unknown 

 there at the time of Nelson's work. Unalaska has long been their 

 northern limit on the Pacific coast. They find shelter about the 

 wharves and lumber piles at St. Michael and also infest the l)uildings, 

 particularly food warehouses. Their distribution will undoulitedly 

 soon be extended all along the Yukon by means of the many steamers 

 now plying between St. Michael and Dawson. 



Peromyscus oreas Bangs. Bangs White-footed Mouse. 

 Peromyscus oreas Bangs, Proc. Biol. Soc. Wash., XII, 84, March 24, 1898. 



Long-tailed mice were taken at Skagway, Glacier, Summit, Bennett, 

 Caribou Crossing, Fifty-Mile River, and Rink Rapids. In general 

 they seemed to be more woodland loving than the short-tailed species, 

 though at Bennett a number were taken among bare rocks at the very 

 water's edge. I first noticed them here while walking along the shore 

 at night. They were darting in and out among the rocks, chasing- 

 each other as if playing a game of tag, and often four or five were in 

 sight at once. jP. otvas from the type locality is somewhat intermedi- 

 ate between my specimens and those which come from the coast of 

 Puget Sound and southern British Columbia. Northern specimens 

 are slightly larger, paler, and less ruddy brown than typical oreas. 

 They are very similar in color to canade7isis and increase the prob- 



