Plates [2], [3], [4], [9], [10], [11] and [41]
Putorius arcticus Merriam, N. Amer. Fauna, 11:15, pl. 2, figs. 1, 1a, and pl. 5, figs. 6, 6a, June 30, 1896.
Putorius (Gale) erminea, Coues, Fur-bearing animals, p. 109, 1877 (part).
Putorius richardsonii, Bangs, Proc. Biol. Soc. Washington, 10:16, pl. 1, figs. 3, 3a, pl. 2, figs. 3, 3a, and pl. 3, figs. 6, 6a, February 25, 1896 (part).
Putorius cicognanii alascensis, Osgood, N. Amer. Fauna, 19:43, October 6, 1900.
Putorius kadiacensis, Osgood, N. Amer. Fauna, 21:69, September 26, 1901.
Putorius audax Barrett-Hamilton, Ann. and Mag. Nat. Hist., 13(ser. 7):392, May, 1904, type from Discovery Bay, Ellesmere Island.
Putorius alascensis, Heller, Univ. California Publ. Zoöl., 5:345, March 5, 1910.
Mustela arctica arctica, Miller, U. S. Nat. Mus. Bull., 79:97, December 31, 1912; Dice, Journ. Mamm., 2:22, February 10, 1921.
Mustela arctica, Hall, Univ. California Publ. Zoöl., 30:420, March 19, 1929.
Mustela erminea arctica, Ognev, The mammals of U.S.S.R. and adjacent countries, 3:31, 1935; Hall, Proc. California Acad. Sci., 23:559, August 22, 1944; Hall, Journ. Mamm., 26:179, July 19, 1945.
Type.—Male, adult, skull and skin; no. 14062/23010, U. S. Nat. Mus.; Point Barrow, Alaska; July 16, 1883; obtained by John Murdock, original no. 1672.
The skull has a fracture, on the dorsal surface, extending from the anterior nares to the interorbital constriction and another fracture on the left margin of the nasal bone. The middle of the left zygomatic arch is broken away. Otherwise the skull is complete. Right incisor one, above and below, are missing. Otherwise the teeth are present and entire. The skin is in the brown summer pelage, well made, in a good state of preservation, and shows no obvious signs of fading.
Range.—Arctic regions of Alaska and western Canada from the Pacific Ocean to Smith Sound; from the northern limit of land south approximately to a line from Skagway through Ft. Goodhope, north shore of Great Bear Lake, south shore of Clinton Colden Lake, north shore of Baker Lake, west end of Wagner Bay to south end of Committee Bay. See figure [25] on page [95].
Characters for ready recognition.—Differs from M. e. polaris in darker upper parts (Raw Umber rather than Buckthorn Brown) and less intensely colored underparts that are Sulphur Yellow, Colonial Buff or Primrose Yellow rather than Buff Yellow; from M. e. semplei, in males, in that hind foot more than 44 and basilar length more than 41 and in that females average larger, the skulls of females being only about 11 per cent heavier; from M. e. kadiacensis in hind foot more than 33 in females, zygomatic breadth amounting to more, rather than less, than distance between last upper molar and jugular foramen irrespective of sex; from M. e. richardsonii, alascensis, salva and initis, both sexes so far as known, by proximal two-thirds of under side of tail colored same as underparts rather than same as upper parts, and by zygomatic breadth amounting to more, rather than less, than distance between last upper molar and jugular foramen.
Description.—Size.—Male: Six adults from Tanana, Alaska, yield average and extreme measurements as follows: Total length, 336 (310-350); length of tail, 93 (84-105); length of hind foot, 49 (45-51).
Female: Five adults, one each from Alatna River, mountains near Eagle, Kamarkak in Alaska, Arctic Red River and Baillie Island in Canada, yield average and extreme measurements as follows: Total length, 285 (272-304); length of tail, 77 (68-95); length of hind foot, 39 (34-43).
Weight of 5 subadult males from Tanana is 206 (163-248) grams; adults would be heavier.
Color.—Winter pelage all white except tip of tail. Summer pelage with upper parts uniform in color and Raw Umber or darker (16n) of Ridgway and about tones 2 to 3 of Chocolate of Oberthür and Dauthenay, pl. 343, but in autumn some specimens have more light red than tones 2 or 3. Underparts Sulphur Yellow, Colonial Buff, or Primrose Yellow, often white on chin and insides of forelegs; color of underparts extends narrowly over upper lips, distally on posterior sides of forelegs onto antipalmar surface of forefeet, onto proximal two-thirds or three-fourths of underside of tail as length of tail is measured along tail-vertebrae, on medial sides of hind legs to a point between knee and ankle but reappears on antiplantar faces of toes and in some individuals is narrowly continuous onto toes; rim of ear in some specimens with short, white or pale hairs giving ears distinct whitish border; least width of color of underparts averaging, in adult males from Alaska, 65 (46-93) per cent of greatest width of color of upper parts. Black tip of tail in 5 males in winter pelage from Tanana averaging 84 (70-93) mm. which is 91 (75-107) per cent of length of tail-vertebrae.
Skull.—Male (based on 5 adult topotypes): See measurements and plates [2]-[4]. As described in Mustela erminea richardsonii except that: Weight, 3.5 (3.1-3.9) grams; basilar length 42.5 (41.8-43.3); length of tooth-rows more than length of tympanic bulla; breadth of rostrum measured across lacrimal processes averaging more than a third of basilar length; interorbital breadth more than distance between glenoid fossa and posterior border of external auditory meatus; zygomatic breadth more than distance between last upper molar and jugular foramen.
Female (based on 2 adult topotypes and 2 adults and 4 subadults from central Alaska): See measurements and plates [9]-[11]. As described in Mustela erminea richardsonii except that: Weight, 1.5 (1.2-2.0) grams; basilar length, 35.7 (34.5-37.0); length of tooth-rows more than length of tympanic bulla; breadth of rostrum more than 30 per cent of basilar length; interorbital breadth more than distance between glenoid fossa and posterior border of external auditory meatus; zygomatic breadth more than distance between last upper molar and jugular foramen (except in specimens from Ellesmere Island where two distances are approximately equal).
Cranial differences from Mustela erminea kaneii (which occurs on the Asiatic side of Bering Strait), in both males and females, are: larger size relatively as well as actually, broader except in mastoidal region where relatively (to basilar length) the width is less; preorbital part of skull broader as well as longer.
From kadiacensis differences in the skull of the male are: size less; 13 per cent heavier, relatively (to basilar length) narrower across interorbital region and zygomatic arches; tympanic bullae relatively as well as actually narrower. Judging by the single available adult female of kadiacensis, the skull of female arctica is larger in all parts measured, a fourth heavier, has tympanic bullae of almost twice the volume and the interorbital and preorbital regions, relative to the braincase, are much reduced in whatever plane measured.
Differences from richardsonii, additional to those noted above in the formal description of the skull, between the males, are: larger in all parts measured except length of tympanic bulla which is about the same; 42 per cent heavier; relative to basilar length, skull broader with preorbital part longer as well as broader; tympanic bullae more inflated posteriorly. The same differences prevail between females except that the skull is 36 per cent heavier and in arctica the length of the bulla is actually more (although relative to the basilar length less) and its greater inflation posteriorly is hardly perceptible. Differences from alascensis, additional to those indicated in the formal descriptions of the skulls of the two, in males, are: larger in every part measured; 95 per cent heavier; relative to the basilar length, skull broader with preorbital part longer as well as broader; measured at a point opposite the foramen lacerum anterius, the width of the pterygoid space is more, rather than less, than 40 per cent of its length. Excepting this difference in width of interpterygoid space, the same differences prevail between females, those of arctica being 56 per cent heavier.
Comparison with semplei is made in the account of that subspecies.
Skull indistinguishable from that of polaris.
Remarks.—The person who studies specimens of this subspecies finds labels inscribed with the names of naturalists well known to all readers of literature on the Arctic. Sir John Franklin, R. McFarlane, R. Kennicott, E. W. Nelson and R. M. Anderson are names which appear commonly. Of Alaskan specimens prepared according to modern methods, a large share was obtained by O. J. Murie and L. R. Dice.