The two adult males from Lillooet, British Columbia, are referable to _oribasus_ although neither is quite typical. One has a saturated coloration suggestive of that of _altifrontalis_ and the skull is shorter and broader than in other specimens of _oribasus_. The female from Lillooet, skin alone, no. 916, Prov. Mus., B. C. is small for _oribasus_. The female, no. 1539, collection of Kenneth Racey, from Alta Lake, in brown winter pelage, in almost every measurement falls nearly midway between _altifrontalis_ and _oribasus_ but slightly nearer the latter. The skull from Chezacut and 3 animals from Wistaria, British Columbia, probably are females and show a greater average size than specimens from farther to the southeast. For example, the basilar length of the skull, 44.8 (44.3 to 45.1), exceeds that of the type specimen. The animals from Wistaria on Ootsa Lake furnish the northwesternmost station of occurrence of which I have record for this subspecies. The northernmost records of occurrence, at "Clearwater River, Peace River, B. C," and at Little Prairie, are furnished by a white skin without skull, no. 257450, U. S. Nat. Mus., purchased on August 2, 1932, at the place mentioned by W. H. Sheldon and Richard Borden, and a skull with white winter skin, no. 3585, Provincial Museum, British Columbia, respectively. The characters distinguishing _longicauda_ and _oribasus_ are not shown by white winter skins; the skull shows some features of _longicauda_, and the reference of these specimens to _oribasus_ rather than _longicauda_ is tentative. Only the skull from Little Prairie shows evidence of infestation of the frontal sinuses by parasites. In the Barkerville area of British Columbia, Mr. and Mrs. Thomas T. McCabe obtained only 2 skulls of this subspecies from a total of 238 weasel skulls gathered by local trappers. The others were _Mustela erminea_. _Specimens examined._--Total number, 46, listed by localities from north to south and unless otherwise indicated, in the United States National Museum. =British Columbia.= West of Hudson Hope, 1[7]; Clearwater River, tributary to Peace River, 1; Little Prairie, a few miles south of Peace River and about 40 miles west of the main highway between Dawson Creek and Fort St. John, 1[85]; Wistaria, 3[85]; Four Mile Creek, 4 mi. NE Quesnel, 1[21]; Isaacs Lake, 3200 ft., 1[74]; Barkerville region, 1[74]; Clear River, 4800 ft., 1[74]; Chezacut, 1[31]; Lillooet 3 (2[77], 1[85]); Alta Lake, 1[31]; source of Kettle River, 7500 ft., 1[75]; E side Beaverfoot Range, 4000 to 4500 ft. between Fraser Creek and 6 mi. SE of Fraser Creek, 1[74]; Cranbrook, 1[86]; head of Cross River, 10 mi. below Assiniboine Pass, 1[7]; camp east of "Kootanie," 1[7]; camp east of Kootanie River, 1[7]. =Alberta.= Thoral Creek, 7000 ft., 50 mi. NE Jasper, 1[2].