_Remarks._--The available specimens of this ermine were obtained by J. H. Keen in 1898, Wilfred H. Osgood and E. A. Lewis in 1900, W. W. Brown in 1914, J. A. Munro in 1917 and 1918, and Allan Brooks in 1920. _M. e. haidarum_ has more claim to full specific status than any other race of ermine because the diagnostic structural features are numerous and individually of relatively great degree. Indeed, individual variation appears not to bridge the gap between any population of _haidarum_ and other subspecies and strong reasons could be advanced for according _haidarum_ the status of a full species. It differs from the subspecies of _erminea_ on the adjoining mainland and adjoining islands to the north and south and agrees with the Arctic races (_arctica_, _polaris_, _semplei_ and _kadiacensis_) in great extent of the color of the underparts, extension of this color onto the underneath side of the tail, long black tip of the tail and general form of the skull including the relatively heavy preorbital region. The color although darker than in the Arctic subspecies, is lighter than in the insular races immediately to the north and south. In combination, the features mentioned could be taken as indication that _haidarum_ is a relict population from a former glacial period. Assuming that it is a relict population, the color may have become slightly darker since that period but the main response appears to have been a decrease in size for this is a much smaller animal than the Arctic ermines. The size is about what would be expected if one were to judge by the slightly larger ermines on the islands of southeastern Alaska to the north and the smaller ermine on Vancouver Island to the south. The ermines of the islands of southeastern Alaska, excepting possibly the incompletely known _seclusa_, have fewer characters of the Arctic races and more characters of the races of the adjoining mainland. Therefore, a possible inference is that the distinctive characters of ermines of the Alaskan islands developed with the aid of isolation from stocks which reached the islands after the glacial period. _M. e. haidarum_ may have found its way to the Queen Charlotte Islands in the glacial period. _Specimens examined._--Total number, 17, as follows. Arranged by locality from north to south. Unless otherwise indicated, specimens are in the U. S. National Museum. =British Columbia.= Queen Charlotte Islands. Masset, 7 (4[74], 1[2], 1[59]); Skidegate, 1; Graham Island, 5 (2[94], 1[77], 1[2]); Cumsheva Inlet, 3; no locality more definite than Queen Charlotte Islands, 1[2]. =Mustela erminea anguinae= Hall Ermine Plates 5, 6, 7, 11, 12 and 13 _Mustela cicognanii anguinae_ Hall, Univ. California Publ. Zoöl., 38:417, November 8, 1932. _Putorius cicognanii_, Baird, Mamm. N. Amer., p. 161, 1858 (part). _Putorius streatori_, Swarth, Univ. California Publ. Zoöl., 10:102, February 13, 1912.