The Project Gutenberg EBook of Mammals taken Along the Alaska Highway, by Rollin H. Baker This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org Title: Mammals taken Along the Alaska Highway Author: Rollin H. Baker Release Date: October 19, 2010 [EBook #33915] Language: English Character set encoding: ISO-8859-1 *** START OF THIS PROJECT GUTENBERG EBOOK MAMMALS TAKEN ALONG THE *** Produced by Chris Curnow, Tom Cosmas, Joseph Cooper and the Online Distributed Proofreading Team at http://www.pgdp.net Transcriber's Notes The text presented is essentially that in the original printed document with the exception of some minor punctuation changes and the typographical corrections detailed below. Typographical Corrections Page 103 (Dawson Red-backed Mouse) :Territoy => Territory Page 104 (Muskrat) : Mann. => Mamm. Page 114 (Red Fox) : procupine => porcupine Mammals Taken Along the Alaska Highway BY ROLLIN H. BAKER University of Kansas Publications Museum of Natural History [Pg 87] Volume 5, No. 9, pp. 87-117, 1 figure in text November 28, 1951 University of Kansas LAWRENCE 1951 University of Kansas Publications, Museum of Natural History Editors: E. Raymond Hall, Chairman, A. Byron Leonard, Edward H. Taylor, Robert W. Wilson Volume 5, No. 9, pp. 87-117, 1 figure in text November 28, 1951 University of Kansas Lawrence, Kansas PRINTED BY FERD VOILAND, JR., STATE PRINTER TOPEKA, KANSAS 1951 23-7607 Mammals Taken Along the Alaska Highway BY ROLLIN H. BAKER INTRODUCTION Mammals from along the Alaska Highway were obtained for the University of Kansas Museum of Natural History in the summers of 1947 and 1948 by Mr. J. R. Alcorn, field representative of the Museum. He and his family visited Alberta, British Columbia, the Yukon Territory and Alaska in an automobile and trailer from June 9, 1947, to September 6, 1947, and again from June 8, 1948, to August 24, 1948. In 1947, considerable time was spent by Alcorn in Alaska; trips were made on the Steese Highway to Circle and on the Glenn Highway to Anchorage. In 1948, most of the collecting was done in British Columbia and in the Yukon Territory but a side trip was taken to Haines, Alaska. The collecting stations are shown in figure 1. Alcorn's 1,252 specimens include several large series from areas where few or no mammals had been taken previously. Time spent at each collecting station was of short duration (usually less than three days) and although 56 species and subspecies of mammals are represented in the collections, it is recognized that not all of the kinds of mammals at any one locality were taken. [Pg 88] [Pg 89] For the loan of comparative mammalian material, grateful acknowledgment is made to officials of the following institutions: California Academy of Sciences; Biological Surveys collection of the U. S. National Museum; Provincial Museum, Victoria, B. C.; National Museum of Canada. The promptness of officials of the game commissions of the provinces and territories concerned, in providing permits for collecting also is acknowledged. A part of the funds for field work was made available by a grant from the Kansas University Endowment Association. Elevations above sea level are given in feet. Capitalized color terms refer to those in Ridgway, Color Standards and Color Nomenclature, Washington, D. C., 1912. Specimen Locality Map FIG. 1. Map showing localities where J. R. Alcorn collected mammals in Alaska, Yukon Territory, British Columbia, and Alberta, in 1947 and 1948. COLLECTING LOCALITIES SHOWN IN FIGURE 1. ALASKA 1. Circle. 2. Twelve Mile Summit, Steese Highway. 3. Chatanika River, 14 mi. E and 25 mi. N Fairbanks. 4. 1 mi. SW Fairbanks. 5. North side Salcha River, 25 mi. S and 20 mi. E Fairbanks. 6. Richardson Highway, 32 mi. S and 4 mi. W Big Delta. 7. Yerrick Creek, 21 mi. W and 4 mi. N Tok Junction. 8. Tok Junction. 9. Fish Creek, 5 mi. N and 1 mi. E Paxson. 10. East side Deadman Lake, 15 mi. SE Northway. 11. Glenn Highway, 6 mi. WSW Snowshoe Lake. 12. 1 mi. NE Anchorage. 13. East side Chilkat River, 9 mi. W and 4 mi. N Haines. 14. 1 mi. S Haines. [Pg 90] [Pg 91] YUKON TERRITORY To avoid undue crowding, or overlapping, of symbols, two or more collecting localities, in some instances, are represented by a single symbol (solid circle) in figure 1. 15. Junction Grafe and Edith Creeks. 16. 6 mi. SW Kluane. 17. East side Aishihik River, 17 mi. N Canyon. 18. 25 mi. NW Whitehorse. 19. { 2 mi. NNW Whitehorse. McIntyre Creek, 3 mi. NW Whitehorse. 1 mi. NE Whitehorse. ½ mi. W Whitehorse. 20. West side Lewes River, 2 mi. S Whitehorse. 21. { Marshall Creek, 3 mi. N Dezadeash River. Champagne, North side Dezadeash Lake. SW end Dezadeash Lake. 22. { 5 mi. W Teslin River, 16 mi. S and 53 mi. E Whitehorse. 2 mi. W Teslin River, 16 mi. S and 56 mi. E Whitehorse. West side Teslin River, 16 mi. S and 58 mi. E Whitehorse. East side Teslin River, 16 mi. S and 59 mi. E Whitehorse. 23. {Unahini River, 5 mi. N and 1 mi. E Dalton Post. Unahini River, 3 mi. N and 1 mi. E Dalton Post. 24. {1½ mi. E Tatshenshini River, 1½ mi. S and 3 mi. E Dalton Post. BRITISH COLUMBIA 25. 1 mi. NW junction of Irons Creek and Liard River. 26. Screw Creek, 10 mi. S and 50 mi. E Teslin. 27. { 15 mi. NW Kelsall Lake. Stonehouse Creek, 5½ mi. W junction Stonehouse Creek and Kelsall River. 28. 14 mi. N Fort Halkett, West side Smith River. 29. West side Mt. Glave, 14 mi. S and 2 mi. E Kelsall Lake. 30. North side Liard River, Fort Halkett. 31. { Hot Springs, 3 mi. WNW junction Trout River and Liard River. North side Liard River, ½ mi. W junction Trout River and Liard River. ¼ mi. S junction Trout River and Liard River. 32. 12 mi. S junction Trout River and Liard River. 33. {NE end Muncho Lake. SE end Muncho Lake. 34. 10 mi. W Fort Nelson. 35. North side Muskwa River, 4 mi. W Fort Nelson. 36. South side Toad River, 10 mi. S and 21 mi. E Muncho Lake. 37. Summit Pass, 10 mi. S and 70 mi. W Fort Nelson. 38. North Fork Tetsa River, 4 mi. ENE Summit Pass. 39. East side Minaker River, 1 mi. W Trutch. 40. Buckinghorse River, 94 mi. S Fort Nelson. 41. Beatton River, 115 mi. S Fort Nelson. 42. 5 mi. W and 3 mi. N Fort St. John. ALBERTA 43. Assineau River, 10 mi. E and 1 mi. N Kinuso. ACCOUNTS OF SPECIES Sorex cinereus cinereus Kerr Cinereous Shrew Sorex arcticus cinereus Kerr, Animal Kingdom, p. 206, 1792. (Type from Fort Severn, Ontario, Canada.) Sorex cinereus cinereus Jackson, Jour. Mamm., 6:56, February 9, 1925. Specimens examined.—Total 56, as follows: Alaska: Chatanika River, 700 ft., 14 mi. E and 25 mi. N Fairbanks, 3; N side Salcha River, 600 ft., 25 mi. S and 20 mi. E Fairbanks, 10; Yerrick Creek, 21 mi. W and 4 mi. N Tok Junction, 2; E side Deadman Lake, 1800 ft., 15 mi. SE Northway, 1. Yukon Territory: 6 mi. SW Kluane, 2550 ft., 1; McIntyre Creek, 2250 ft., 3 mi. NW Whitehorse, 2; W side Lewes River, 2150 ft., 2 mi. S Whitehorse, 2; SW end Dezadeash Lake, 4; 1½ mi. S and 3 mi. E Dalton Post, 2500 ft., 10. British Columbia: Stonehouse Creek, 5½ mi. W jct. Stonehouse Creek and Kelsall River, 9; Hot Springs, 3 mi. WNW jct. Trout River and Liard River, 6; ¼ mi. S jct. Trout River and Liard River, 4; 5 mi. W and 3 mi. N Fort St. John, 1. Alberta: Assineau River, 1920 ft., 10 mi. E and 1 mi. N Kinuso, 1. [Pg 92] Remarks.—Shrews from extreme northwestern British Columbia (Stonehouse Creek) average slightly larger than typical S. c. cinereus, especially in length of tail. These animals show definite evidence of intergradation with the larger subspecies, S. c. streatori, but are referable to S. c. cinereus. The pallor of some shrews from east-central Alaska (Chatanika River and Salcha River) suggests intergradation with the pale S. c. hollisteri. Alcorn found the cinereous shrew at most of his trapping stations. It was captured in mouse traps baited with "chewed" rolled oats; one was taken in a trap baited with a grasshopper. Rand (1944:35) and Alcorn each found this shrew to be one of the commoner mammals along the Alaska Highway, but Alcorn did not find it to be so abundant as some of the rodents in areas in which he trapped. The cinereous shrew was taken principally in moist woodlands, grassy areas, and adjacent to water. One female taken on July 18 was lactating. Sorex cinereus streatori Merriam Cinereous Shrew Sorex personatus streatori Merriam, N. Amer. Fauna, 10:62, December 31, 1895. (Type from Yakutat, Alaska.) Sorex cinereus streatori Jackson, Jour. Mamm., 6:56, February 9, 1925. Specimens examined.—Total 19, as follows: Alaska: E side Chilkat River, 100 ft., 9 mi. W and 4 mi. N Haines, 10; 1 mi. S Haines, 5 ft., 9. Remarks.—Average and extreme external measurements of the nine adult specimens from 1 mile south of Haines are as follows: Total length, 103 (98-105); tail, 45 (43-46); and condylobasal length, 16.2 (16.0-16.4). Corresponding measurements of an adult specimen (No. 1676, UKMNH) from Sitka, Alaska, are 108, 47, and 16.5. Measurements of ten adult specimens from the Chilkat River, 9 miles west and 4 miles north of Haines, are 100 (91-106), 44 (40-50), 16.0 (15.5-16.5). The slightly smaller average size of the latter specimens indicates a trend toward the smaller S. c. cinereus, which occurs farther inland. Skulls of some of the specimens from the Chilkat River have a more slender rostrum than those of the specimens from 1 mile south of Haines, and more nearly resemble S. c. cinereus in this respect. Evidently, as indicated by Jackson (1928:54), S. c. streatori occupies only an extremely narrow strip of mainland in the vicinity of Haines. Sorex cinereus hollisteri Jackson Cinereous Shrew Sorex cinereus hollisteri Jackson, Jour. Mamm., 6:55, February 9, 1925. (Type from St. Michael, Alaska.) Specimens examined.—Two from Alaska: 1 mi. NE Anchorage, 100 ft. Remarks.—Both specimens of this pale subspecies were trapped, along with six Clethrionomys and one Mus, in a grassy area bordered on one side by the road and on the other by a spruce forest. No. 21069, ♂?, taken on August 21, is in molt, with one patch of new fur on the rump and another along the midline of the nape and shoulders. Sorex obscurus obscurus Merriam Dusky Shrew Sorex obscurus Merriam, N. Amer. Fauna, 10:72, December 31, 1895. (Type from near Timber Creek, altitude 8200 ft., Salmon River Mountains, now Lemhi Mountains, 10 miles west of Junction, Lemhi County, Idaho.) Specimens examined.—Total 12, as follows: Yukon Territory: McIntyre Creek, 2250 ft., 3 mi. NW Whitehorse, 1; SW end Dezadeash Lake, 2; 1½ mi. S and 3 mi. E Dalton Post, 2500 ft., 1. British Columbia: Stonehouse Creek, 5½ mi. W jct. Stonehouse Creek and Kelsall River, 4; W side Mt. Glave, 4000 ft., 14 mi. S and 2 mi. E Kelsall Lake, 1; Hot Springs, 3 mi. WNW jct. Trout River and Liard River, 1. Alberta: Assineau River, 1920 ft., 10 mi. E and 1 mi. N Kinuso, 2. Remarks.—Some of the shrews taken in extreme southwestern Yukon Territory (1½ miles south and 3 miles east of Dalton Post) and in extreme northwestern British Columbia (Stonehouse Creek and Mt. Glave) show evidence of intergradation with the coastal subspecies, S. o. alascensis, in length of hind foot. These individuals have a long hind foot (14 and 15); the hind feet of specimens from the other localities listed measure 13 and 14. Alcorn, like Rand (1944:35), found the dusky shrew to be less common than the cinereous shrew; both were taken in the same trap lines. The dusky shrew was taken at a higher altitude (4000 feet, on Mt. Glave) than the cinereous shrew. Sorex obscurus shumaginensis Merriam [Pg 93] [Pg 94] Dusky Shrew Sorex alascensis shumaginensis Merriam, Proc. Washington Acad. Sci., 2:18, March 14, 1900. (Type from Popof Island, Shumagin Islands, Alaska.) Sorex obscurus shumaginensis J. A. Allen, Bull. Amer. Mus. Nat. Hist, 16:228, July 12, 1902. Specimens examined.—Total 3, as follows: Alaska: 1 mi. NE Anchorage, 100 ft., 1; Glenn Highway, 6 mi. WSW Snowshoe Lake, 2. Remarks.—These three shrews, in comparison with those referred to S. o. obscurus, are paler, and the one complete skull has a slightly higher braincase. All of the specimens were obtained in grassy areas adjacent to the roadway. Sorex obscurus alascensis Merriam Dusky Shrew Sorex obscurus alascensis Merriam, N. Amer. Fauna, 10:76, December 31, 1895. (Type from Yakutat, Alaska.) Specimens examined.—Total 22, as follows: Alaska: E side Chilkat River, 100 ft., 9 mi. W and 4 mi. N Haines, 12; 1 mi. S Haines, 5 ft., 10. Sorex palustris navigator (Baird) Water Shrew Neosorex navigator Baird, Report Pacific R. R. Survey, 8, pt. 1, Mammals, p. 11, 1857. (Type from near head of Yakima River, Cascade Mountains, Washington.) Sorex (Neosorex) palustris navigator Merriam, N. Amer. Fauna, 10:92, December 31, 1895. Specimens examined.—Total 20, as follows: Alaska: E side Chilkat River, 100 ft., 9 mi. W and 4 mi. N Haines, 2. Yukon Territory: McIntyre Creek, 2250 ft., 3 mi. NW Whitehorse, 11; SW end Dezadeash Lake, 2; 1½ mi. S and 3 mi. E Dalton Post, 2500 ft., 3. British Columbia: Stonehouse Creek, 5½ mi. W jct. Stonehouse Creek and Kelsall River, 2. Remarks.—Those males with worn teeth seem to have a slightly longer and deeper rostrum with a larger, more inflated cranium than specimens of S. p. navigator from Washington, but in other ways resemble typical S. p. navigator. An adult male, with slightly worn teeth, from Dezadeash Lake has sagittal and lambdoidal crests. All of the water shrews were taken in July and early August and at the edge of water in traps baited with rolled oats. None of the females had embryos. Myotis lucifugus lucifugus (LeConte) Little Brown Bat Vespertilio lucifugus LeConte, McMurtrie's Cuvier, Animal Kingdom, vol. 1, appendix, p. 431, 1831. (Type from Georgia; probably the LeConte plantation, near Riceboro, Liberty County.) Myotis lucifugus Miller, N. Amer. Fauna, 13:59, October 16, 1897. Specimens examined.—Thirty-eight from British Columbia: NE end Muncho Lake. Remarks.—The 38 bats were from a colony of approximately 75 individuals, found on the south side of a house. The paper was loose and had buckled in numerous places allowing room for the bats to ensconce themselves between the paper and outside wall. Myotis lucifugus alascensis Miller Little Brown Bat Myotis lucifugus alascensis Miller, N. Amer. Fauna, 13:63, October 16, 1897. (Type from Sitka, Alaska.) Specimens examined.—One from British Columbia: Screw Creek, 10 mi. S and 50 mi. E Teslin. Remarks.—The specimen is considerably darker both above and below than either of two specimens of M. l. alascensis from Red Bluff Bay, Alaska. Alcorn searched ten frame buildings in an abandoned camp on the east side of Screw Creek, for bats and found only the one bat. It was above some droppings. No droppings were found in other buildings. [Pg 95] Ochotona collaris (Nelson) Collared Pika Lagomys collaris Nelson, Proc. Biol. Soc. Washington, 8:117, December 21, 1893. (Type from near head of Tanana River, about 200 miles south of Fort Yukon, Alaska.) [Ochotona] collaris Trouessart, Catal. Mamm. viv. foss., p. 648, 1897. Specimens examined.—Total 14, as follows: British Columbia: Stonehouse Creek, 5½ mi. W jct. Stonehouse Creek and Kelsall River, 1; W side Mt. Glave, 4000 ft., 14 mi. S and 2 mi. E Kelsall Lake, 13. Remarks.—In comparing specimens obtained by Alcorn with published descriptions of O. collaris in Howell (1924:35), it appeared that measurable geographic variation might be present in this monotypic species. Accordingly, comparisons were made with materials in the Biological Surveys collection of the U. S. National Museum, the Provincial Museum, Victoria, B. C., and the National Museum of Canada. A comparison of specimens of similar ages showed that no subspecific separation is justified although animals from the Yukon Territory, British Columbia, and Northwest Territories, as compared with available material from Alaska, tend to be grayer in color and longer in total length with a slightly larger skull and greater alveolar length of molariform tooth-row in both upper and lower jaws. Specimens used for comparison were from the following localities: Alaska: Mts. near Eagle (USBS), 15; 200 mi. S Fort Yukon (USBS), 2; Upper Little Delta River, Glacier Creek, Mt. Hayes region (USBS), 1; Glacier Creek, Mt. Hayes region (USBS), 3; Little Delta River, Slate Creek, Red Mt. Camp, Mt. Hayes region (USBS), 1; Muldron Glacier, Mt. McKinley (USBS), 2; Mt. McKinley (USBS), 3; Summit of Chugach Mts., on Richardson Highway, N of Valdez (USBS), 1; Chitina River Glacier (Nat. Mus. Canada), 3. Yukon Territory: McMillan Pass, Canol Road, mile 282 (Nat. Mus. Canada), 2; Rose River, Canol Road, mile 95 (Nat. Mus. Canada), 8; Tepee Lake (Nat. Mus. Canada), 1; Conrad (Nat. Mus. Canada), 1; near Teslin Lake (Nat. Mus. Canada), 1. Northwest Territories: headwaters of Caracajou River, Canol Road, mile 111E (Nat. Mus. Canada), 1. British Columbia: White Mt., Moose Arm, Tagish Lake, Atlin (Prov. Mus., Victoria, B.C.), 2. Lepus americanus macfarlani Merriam Varying Hare Lepus americanus macfarlani Merriam, Proc. Washington Acad. Sci., 2:30, March 14, 1900. (Type from Fort Anderson, near mouth of Anderson River, Mackenzie, Canada.) Specimens examined.—Total 3, as follows: Yukon Territory: W side Lewes River, 2150 ft., 2 mi. S Whitehorse, 1; 5 mi. W Teslin River, 2400 ft., 16 mi. S and 53 mi. E Whitehorse, 1. British Columbia: 14 mi. N Fort Halkett, W side Smith River, 1. Remarks.—Alcorn reports seeing few hares on his two trips to Alaska. Near the Miniker River, a geologist told him that the numbers of these animals had steadily declined since 1943. One of three seen in a spruce forest on July 8, 1947, near Whitehorse was taken by Alcorn. A young one was captured in a rat trap in a building near the Teslin River on July 5 of the same year. Tamiasciurus hudsonicus columbiensis A. H. Howell Red Squirrel Tamiasciurus hudsonicus columbiensis A. H. Howell, Proc. Biol. Soc. Washington, 49:135, August 22, 1936. (Type from Raspberry Creek, about 30 mi. SE of Telegraph Creek, northern British Columbia.) Specimens examined.—Total 18, as follows: Yukon Territory: McIntyre Creek, 2250 ft., 3 mi. NW Whitehorse, 1; W side Lewes River, 2150 ft., 2 mi. SW Whitehorse, 1; 2 mi. W Teslin River, 2400 ft., 16 mi. E Whitehorse, 1. British Columbia: 1 mi. NW jct. Irons Creek and Liard River, 1; ¼ mi. S jct. Trout River and Liard River, 3; S side Toad River, 10 mi. S and 21 mi. E Muncho Lake, 3; Summit Pass, 4200 ft., 10 mi. S and 70 mi. W Fort Nelson, 8. Remarks.—Rand (1944:42) experienced difficulty in assigning subspecific names to red squirrels taken along the Alaska Highway in northern British Columbia. Some variability as found by Rand is noted in adults taken by Alcorn in this area. All of the specimens assigned to T. h. columbiensis have a darker tail and more tawny feet than T. h. preblei. The average of skulls of adults is smaller than the skull of an adult of T. h. preblei from Yerrick Creek, Alaska. Alcorn obtained most of the squirrels in rat traps and steel traps, using "chewed" rolled oats as well as bits of fish and mouse bodies as bait. Tamiasciurus hudsonicus petulans (Osgood) Red Squirrel Sciurus hudsonicus petulans Osgood, N. Amer. Fauna, 19:27, October 6, 1900. (Type from Glacier, White [Pg 96] [Pg 97] Pass, Alaska.) T[amiasciurus]. hudsonicus petulans A. H. Howell, Proc. Biol. Soc. Washington, 49:136, August 22, 1936. Specimens examined.—Total 7, as follows: Alaska: 1 mi. S Haines, 5 ft., 2. Yukon Territory: SW end Dezadeash Lake, 1; 1½ mi. E Tatshenshini River, 1½mi. S and 3 mi. E Dalton Post, 4. Remarks.—Specimens from extreme southwestern Yukon Territory appear to be referable to this subspecies. The one adult female (skull only, with body measurements) from the southwestern end of Dezadeash Lake has a shorter skull than does any adult female of T. h. columbiensis. No skins of adults are in the series, but the skins of three subadults have darker upper parts, a darker tail and less olivaceous sides than T. h. columbiensis. Tamiasciurus hudsonicus preblei A. H. Howell Red Squirrel Tamiasciurus hudsonicus preblei A. H. Howell, Proc. Biol. Soc. Washington, 49:133, August 22, 1936. (Type from Fort Simpson, Mackenzie District, Northwestern Territories.) Specimens examined.—Total 3, as follows: Alaska: Chatanika River, 700 ft., 14 mi. E and 25 mi. N Fairbanks, 1; N side Salcha River, 600 ft., 25 mi. S and 20 mi. E Fairbanks, 1; Yerrick Creek, 21 mi. W and 4 mi. N Tok Junction, 1. Remarks.—In comparison with specimens of T. h. hudsonicus from Iskwasum Lake, District of the Pas, Manitoba, the squirrel from Yerrick Creek, an adult female, is larger and paler on the upper parts and tail. The squirrel taken at Yerrick Creek was captured in a rat trap; Alcorn found these animals to be "fairly common" in that area. He obtained no evidence that the natives use them for food. Marmota monax ochracea Swarth Woodchuck Marmota ochracea Swarth, Univ. California Publ. Zoöl., 7:203, February 18, 1911. (Type from Forty-mile Creek, Alaska.) Marmota monax ochracea A. H. Howell, N. Amer. Fauna, 37:34, April 7, 1915. Specimens examined.—Total 3, as follows: British Columbia: Hot Springs, 3 mi. WNW jct. Trout River and Liard River, 1; ¼ mi. S jct. Trout River and Liard River, 2. Citellus parryii plesius (Osgood) Parry Ground Squirrel Spermophilis empetra plesius Osgood, N. Amer. Fauna, 19:29, October 6, 1900. (Type from Bennett City, head of Lake Bennett, British Columbia.) Citellus paryii plesius A. H. Howell, N. Amer. Fauna, 56:97, May 18, 1938. Specimens examined.—Total 42, as follows: Alaska: Richardson Highway, 2000 ft., 32 mi. S and 4 mi. W Big Delta, 5. Yukon Territory: 6 mi. SW Kluane, 2550 ft., 1; McIntyre Creek, 2250 ft., 3 mi. NW Whitehorse, 1; 2 mi. NNW Whitehorse, 2100 ft., 1; 1 mi. NE Whitehorse, 1; ½ mi. W Whitehorse, 2150 ft., 1; SW end Dezadeash Lake, 1; 2 mi. W Teslin River, 2400 ft., 16 mi. S and 56 mi. E Whitehorse, 7; 1½ mi. E Tatshenshini River, 1½ mi. S and 3 mi. E Dalton Post, 3. British Columbia: Stonehouse Creek, 5½ mi. W jct. Stonehouse Creek and Kelsall River, 14; W side Mt. Glave, 4000 ft., 14 mi. S and 2 mi. E Kelsall Lake, 7. Remarks.—The specimens vary much in color; most color variation is the result of wear and fading. In pallor of coloration the specimens taken on August 16 along the Richardson Highway, 32 miles south and 4 miles west of Big Delta, Alaska, show some resemblance to C. p. ablusus, which occurs to the westward, although in other diagnostic characters these specimens are typically C. p. plesius. Specimens in early stages of molt were taken on July 3, 4, and 14; another specimen in an advanced stage of molt was obtained on July 10. One melanistic individual was taken one mile northeast of Whitehorse on July 11. Alcorn found these ground squirrels locally abundant, especially in the vicinity of Whitehorse in Yukon Territory. A large population was observed along the highway west of the Teslin River; animals were seen for several miles along the road, principally in open coniferous forests where there was little or no underbrush. Alcorn caught several animals near the city dump at Whitehorse. Along the Richardson Highway he observed these ground squirrels almost continuously for approximately ten miles. He comments that the animals appeared to be more numerous in the man-cleared areas along the highway than in "unmolested areas farther back from the highway." Specimens were taken with collecting gun and in rat traps baited with "chewed" rolled oats. [Pg 98] [Pg 99] Eutamias minimus borealis (J. A. Allen) Least Chipmunk Tamias asiaticus borealis J. A. Allen, Monogr. N. Amer. Rodentia, p. 793, August, 1877. (Type from Fort Liard, Mackenzie, Canada.) Eutamias minimus borealis A. H. Howell, Jour. Mamm., 3:183, August 4, 1922. Specimens examined.—Total 10, as follows: British Columbia: N side Muskwa River, 1200 ft., 4 mi. W Fort Nelson, 1; E side Minaker River, 1 mi. W Trutch, 5; Beatton River, 115 mi. S Fort Nelson, 1; 5 mi. W. and 3 mi. N Fort St. John, 1. Alberta: Assineau River, 1920 ft., 10 mi. E and 1 mi. N Kinuso, 2. Remarks.—Specimens with worn pelage are conspicuously paler and grayer than those in fresh pelage. Chipmunks in early stages of molt with fresh pelage extending posteriorly to the middle of the dorsal part of the back were taken on June 19, 20, and 22; others in fresh pelage above, except for the hind quarters, were taken on June 15 and on September 2. Alcorn found this species nowhere abundant; for example, in 187 museum special traps set near Charlie Lake, 5 miles west and 3 miles north of Fort St. John, in British Columbia, he took only one chipmunk. Eutamias minimus caniceps Osgood Least Chipmunk Eutamias caniceps Osgood, N. Amer. Fauna, 19:28, October 6, 1900. (Type from Lake Lebarge, Yukon Territory.) Eutamias minimus caniceps A. H. Howell, Jour. Mamm., 3:184, August 4, 1922. Specimens examined.—Total 36, as follows: Yukon Territory: 6 mi. SW Kluane, 2550 ft., 2; McIntyre Creek, 2250 ft., 3 mi. NW Whitehorse, 3; 2 mi. NNW Whitehorse, 2100 ft., 1; W side Lewes River, 2150 ft., 2 mi. S Whitehorse, 1; SW end Dezadeash Lake, 10; 5 mi. W Teslin River, 2400 ft., 16 mi. S and 53 mi. E Whitehorse, 1; W side Teslin River, 16 mi. S and 58 mi. E Whitehorse, 2; 1½ mi. S and 3 mi. E Dalton Post, 2500 ft., 5. British Columbia: 1 mi. NW jct. Irons Creek and Liard River, 2; S side Toad River, 10 mi. S and 21 mi. E Muncho Lake, 6; Summit Pass, 4200 ft., 10 mi. S and 70 mi. W Fort Nelson, 3. Remarks.—Some of the specimens taken between Summit Pass and Toad River show evidence of intergradation between the paler and grayer E. m. caniceps and the brighter and browner E. m. borealis. Rand (1944:41) also found evidence of intergradation between these two subspecies in this area. Along the highway, Alcorn found this species to be somewhat more abundant in the Yukon Territory than in British Columbia. He often found the animals occupying abandoned road camps; seemingly they were more numerous in these areas than in undisturbed natural habitat. Glaucomys sabrinus zaphaeus (Osgood) Flying Squirrel Sciuropterus alpinus zaphaeus Osgood, Proc. Biol. Soc. Washington, 18:133, April 18, 1905. (Type from Helm Bay, Cleveland Peninsula, southeastern Alaska.) Glaucomys sabrinus zaphaeus A. H. Howell, N. Amer. Fauna, 44:43, June 13, 1918. Specimens examined.—One from Yukon Territory: 1½ mi. S and 3 mi. E Dalton Post, 2500 ft. Remarks.—Although comparative material is not available at this writing, descriptions in the literature indicate that this single adult female belongs to the coastal form, G. s. zaphaeus. In both color and in cranial and external measurements, this specimen appears to agree closely with descriptions given by Howell (1918:43) and by Cowan (1937:78 and 82), although its measurements are also in the range of those given for G. s. alpinus by Cowan (loc. cit.). It may be pointed out that Swarth (1936:402) regarded a specimen from 15 miles south of Atlin, British Columbia, as G. s. alpinus. Measurements of Alcorn's specimen are as follows: total length, 331; tail, 143; hind foot, 42; ear from notch, 23; greatest length of skull, 41.7; zygomatic breadth, 25.7; mastoid breadth, 21.7; length of nasals, 12.2; length maxillary tooth-row, 8.2; interorbital constriction, 8.2; and postorbital constriction, 9.0. Castor canadensis sagittatus Benson Beaver Castor canadensis sagittatus Benson, Jour. Mamm., 14:320, November 13, 1933. (Type from Indianpoint [Pg 100] [Pg 101] Castor canadensis sagittatus Benson, Jour. Mamm., 14:320, November 13, 1933. (Type from Indianpoint Creek, 3200 ft., 16 mi. NE Barkerville, British Columbia.) Specimens examined.—Two from British Columbia: Fort Halkett, N side Liard River. Remarks.—Two beaver skulls obtained by Alcorn from trapper Johnny Pie appear to be of this subspecies. Anderson (1947:133) records this subspecies from the Liard River, in the area from which these specimens were taken. The trapper told Alcorn that he shot these two beavers in the winter of 1947-48 and hung the skulls in a tree. Peromyscus maniculatus algidus Osgood White-footed Mouse Peromyscus maniculatus algidus Osgood, N. Amer. Fauna, No. 28:56, April 17, 1909. (Type from head of Lake Bennett, site of old Bennett City, British Columbia.) Specimens examined.—Total 93, as follows: Alaska: E side Chilkat River, 100 ft., 9 mi. W and 4 mi. N Haines, 20; 1 mi. W Haines, 5 ft., 7. Yukon Territory: 6 mi. SW Kluane, 2550 ft., 10; McIntyre Creek, 2250 ft., 3 mi. NW Whitehorse, 6; 2 mi. NNW Whitehorse, 2100 ft., 2; W side Lewes River, 2150 ft., 2 mi. S Whitehorse, 16; SW end Dezadeash Lake, 9; 1½ mi. S and 3 mi. E Dalton Post, 15. British Columbia: Stonehouse Creek, 5½ mi. W jct. Stonehouse Creek and Kelsall River, 8. Remarks.—Specimens from the localities listed above are in the geographic range of P. m. algidus as outlined by Anderson (1947: 136). Specimens from the vicinity of Haines, Alaska, are slightly darker indicating intergradation with P. m. hylaeus; Osgood (1909a: 54 and 56) also noted that intergradation between P. m. algidus and P. m. hylaeus occurs in this area. Peromyscus maniculatus borealis Mearns White-footed Mouse Peromyscus maniculatus borealis Mearns, Proc. Biol. Soc. Washington, 24:102, May 15, 1911. Substitute name for P. m. arcticus Mearns. (Type from Fort Simpson, Mackenzie, Canada.) Specimens examined.—Total 214, as follows: Yukon Territory: 2 mi. W Teslin River, 2400 ft., 16 mi. S and 56 mi. E Whitehorse, 8; W side Teslin River, 2300 ft., 16 mi. S and 58 mi. E Whitehorse, 24; E side Teslin River, 2300 ft., 16 mi. S and 59 mi. E Whitehorse, 7. British Columbia: 1 mi. NW jct. Irons Creek and Liard River, 10; Hot Springs, 3 mi. WNW jct. Trout River and Liard River, 6; N side Liard River, ½ mi. W jct. Trout River and Liard River, 13; ¼ mi. S jct. Trout River and Liard River, 20; SE end Muncho Lake, 5; S side Toad River, 10 mi. S and 21 mi. E Muncho Lake, 45; N side Muskwa River, 1200 ft., 4 mi. W Fort Nelson, 9; North Fork Tetsa River, 3900 ft., 4 mi. ENE Summit Pass, 13; Summit Pass, 4200 ft., 10 mi. S and 70 mi. W Fort Nelson, 17; E side Minaker River, 1 mi. W Trutch, 18; Beatton River, 115 mi. S Fort Nelson, 2; 5 mi. W and 3 mi. N Fort St. John, 7. Alberta: Assineau River, 1920 ft., 10 mi. E and 1 mi. N Kinuso, 10. Remarks.—Specimens from 2 miles west of Teslin River resemble P. m. borealis more than P. m. algidus both in size of skull and in color, although I find it difficult to distinguish the specimens by color. Alcorn, like Rand (1945:43), found the mouse in almost every habitat along the Alaska Highway. On the east side of the Minaker River, one mile west of Trutch, Alcorn took 26 Peromyscus and four Microtus in 70 museum special traps baited with chewed rolled oats, set in a grassy area where there were birches and clumps of willows. Peromyscus was usually abundant in old construction camps along the highway; on July 27 in 50 traps set under abandoned buildings at Summit Pass, Alcorn took 21 Peromyscus. Apparently, as Swarth (1936:402) notes, the white-footed mouse makes itself at home in such buildings, and local populations probably increase as a result of the artificial environment that provides favorable conditions for existence. Neotoma cinerea drummondii (Richardson) Bushy-tailed Wood Rat Myoxus drummondii Richardson, Zool. Jour., 3:517, 1828. (Type probably from near Jasper House, Alberta, Canada.) Neotoma cinerea drummondii Merriam, Proc. Biol. Soc. Washington, 7:25, April 13, 1892. Specimens examined.—Total 4, as follows: British Columbia: Summit Pass, 4500 ft., 10 mi. S and 70 mi. W of Fort Nelson, 1; 5 mi. W and 3 mi. N Fort St. John, 3. Remarks.—Wood rats were obtained at only two locations, Alcorn's field notes indicating that the animals were rare and spotty in distribution. Rand (1944:44) comments that the rats were "scarce north of the Lower Liard Crossing." At both localities where specimens were taken, Alcorn noted first their characteristic droppings. At Summit Pass, droppings were found in a rock slide at the upper limit of timber line; one rat was taken. At the trapping station five [Pg 102] miles west and three miles north of Fort St. John, droppings were found in and under an old abandoned building; four young (two prepared) and one adult were obtained. Synaptomys borealis dalli Merriam Northern Bog Lemming Synaptomys (Mictomys) dalli Merriam, Proc. Biol. Soc. Washington, 10:62, March 19, 1896. (Type from Nulato, Alaska.) Synaptomys borealis dalli A. B. Howell, N. Amer. Fauna, 50:24, (June 30) August 5, 1927. Specimens examined.—Total 6, as follows: Alaska: E side Deadman Lake, 1800 ft., 15 mi. SE Northway, 1. Yukon Territory: McIntyre Creek, 2250 ft., 3 mi. NW Whitehorse, 5. Remarks.—The northern bog lemming is evidently not generally distributed along the Alaska Highway but may be locally numerous in cover of grass and sedge especially in marsh and bog habitat. Five specimens were obtained in a grassy area 30 feet wide by 60 feet long which was approximately 50 feet from McIntyre Creek in the Yukon Territory. In 22 mouse traps set the first night in this locality, three Synaptomys, six Microtus and one Sorex were taken. One additional Synaptomys was taken on each of the following two nights in the same area. At Deadman Lake, Alaska, one Synaptomys was taken in heavy sedge bordering a small pond. Clethrionomys rutilus dawsoni (Merriam) Dawson Red-backed Mouse Evotomys dawsoni Merriam, Amer. Nat., 22:650, July, 1888. (Type from Finlayson River, a northern source of the Liard River, lat. 61° 30' N, long. 129° 30' W, Yukon, Canada.) Clethrionomys rutilus dawsoni Rausch, Jour. Washington Acad. Sci., 40:135, April 21, 1950. Specimens examined.—Total 126, as follows: Alaska: Chatanika River, 700 ft., 14 mi. E and 25 mi. N Fairbanks, 17; 1 mi. SW Fairbanks, 440 ft., 1; N side Salcha River, 600 ft., 25 mi. S and 20 mi. E Fairbanks, 15; 25 mi. S and 20 mi. E Fairbanks, 3; Yerrick Creek, 21 mi. W and 4 mi. N Tok Junction, 32; Tok Junction, 1600 ft., 1; E side Deadman Lake, 1800 ft., 15 mi. SE Northway, 9; 1 mi. NE Anchorage, 100 ft., 9; Glenn Highway, 6 mi. WSW Snowshoe Lake, 1; E side Chilkat River, 100 ft., 9 mi. W and 4 mi. N Haines, 2; 1 mi. S Haines, 5 ft., 2. Yukon Territory: Jct. Grafe Creek and Edith Creek, 2; 6 mi. SW Kluane, 2250 ft., 4; 2 mi. NNW Whitehorse, 2100 ft., 2; W side Lewes River, 2150 ft., 2 mi. S Whitehorse, 6; SW end Desadeash Lake, 15. British Columbia: Stonehouse Creek, 5½ mi. W jct. Stonehouse Creek and Kelsall River, 1; S side Toad River, 10 mi. S and 21 mi. E Muncho Lake, 2; Summit Pass, 4500 ft., 10 mi. S and 70 mi. W Fort Nelson, 2. Remarks.—Specimens from one mile northeast of Anchorage show little tendency toward C. r. orca from the Prince William Sound area (see Orr, 1945:73). One specimen from this locality is slightly darker than the others. Red-backed mice were numerous in most localities where Alcorn trapped. A number of specimens were taken adjacent to and within abandoned road camps, where second growth vegetation was rank. As in the case of C. gapperi, he found C. rutilus in varied habitats. Clethrionomys gapperi athabascae (Preble) Red-backed Mouse Evotomys gapperi athabascae Preble, N. Amer. Fauna, 27:178, October 26, 1908. (Type from Fort Smith, Slave Lake, Mackenzie District, Northwest Territories, Canada.) Clethrionomys gapperi athabascae Harper, Jour. Mamm., 13:28, February 9, 1932. Specimens examined.—Total 14, as follows: British Columbia: N side Muska River, 1200 ft., 4 mi. W Fort Nelson, 1; E side Minaker River, 1 mi. W Trutch, 3; 5 mi. W and 3 mi. N Fort St. John, 4. Alberta: Assineau River, 1920 ft., 10 mi. E and 1 mi. N Kinuso, 6. Remarks.—These red-backed mice were taken in various habitats: grassy areas in aspen and poplar forest, heavy spruce forest with no undergrowth excepting lichens and moss, thick underbrush in river flood plain, and at the site of an old sawmill. The northwestern distribution of this species along the Alaska Highway as found by Alcorn is approximately the same as that found by Rand (1944:44). Ondatra zibethicus spatulatus (Osgood) Muskrat Fiber spatulatus Osgood, N. Amer. Fauna, 19:36, October 6, 1900. (Type from Lake Marsh, Yukon, Canada.) [Pg 103] [Pg 104] Ondatra zibethica spatulata Miller, N. Amer. Land Mamm. 1911, p. 231, December 31, 1912. Specimens examined.—Total 2, as follows: Alaska: N side Salcha River, 600 ft., 25 mi. S and 20 mi. E Fairbanks, 1; E side Deadman Lake, 1800 ft., 15 mi. NE Northway, 1. Remarks.—One muskrat was shot in an old beaver pond on the north side of the Salcha River. A skull from a carcass, that had been left by a trapper the previous winter, was obtained at Deadman Lake. Phenacomys intermedius mackenzii Preble Lemming Mouse Phenacomys mackenzii Preble, Proc. Biol. Soc. Washington, 15:182, August 6, 1902. (Type from Fort Smith, Slave River, Mackenzie, Canada.) Phenacomys intermedius mackenzii Crowe, Bull. Amer. Mus. Nat. Hist, 80:403, February 4, 1943. Specimen examined.—One from Yukon Territory: SE end Dezadeash Lake. Remarks.—A subadult taken only a few miles from the Alaskan border in Yukon Territory constitutes an extension of the known range of this species to the northwest. The mouse is evidently rare or irregular in its distribution since Alcorn did considerable trapping in the area from which only one was taken. Microtus pennsylvanicus Pennsylvania Meadow Mouse The Pennsylvania meadow mouse is an abundant mammal along the Alaska Highway. Alcorn obtained specimens at most of his trapping stations, frequently in company with Microtus oeconomus at the more northern localities. A preferred habitat was grassy areas and willow clumps along streams or at the edges of lakes. The best catches were made along well-used runways, especially where there were piles of cut grass. These runways were used also by Clethrionomys and other small animals. Specimens of M. pennsylvanicus were frequently taken in the daytime; one was taken on June 29 as it was swimming at the edge of a small lake near the junction of the Liard River and Irons Creek in British Columbia. Lacking sufficient comparative material in the past, most workers have considered that M. pennsylvanicus ranges without appreciable geographic variation throughout most of northwestern Canada and Alaska, where it has been referred to the subspecies, M. p. drummondii. Dale (1940), in studying collections made in British Columbia and southeastern Alaska, found evidence of geographic variation and recognized two new subspecies; thus he not only pointed out geographically variable characters but reduced the size of the range ascribed to M. p. drummondii. A later work by Rand (1943) considered the northwestern populations of M. pennsylvanicus as being too variable to show distinctive groupings. The large collection made by Alcorn offers evidence that other separable subspecies with constant characters are present. Study of this material indicates the presence of two unnamed subspecies, which are named and described as follows: Microtus pennsylvanicus alcorni new subspecies Type.—Female, adult, skin with skull, No. 21552, Univ. Kansas, Mus. Nat. Hist., 6 mi. SW Kluane, 2550 feet elevation, Yukon Territory, Canada; 24 August 1947; obtained by J. R. Alcorn; original No. 5240. Range.—Extreme southwestern Yukon Territory and adjacent parts of Alaska as far south as Haines, as far north as Northway, and as far west along the Alaskan coast as Anchorage and Tyonek. Diagnosis.—Size large (see measurements); color of upper parts near (l) Brussels Brown; skull noticeably ridged; zygomatic arches heavy, rounded and relatively short; rostrum heavy; auditory bullae not greatly expanded; maxillary teeth relatively heavy and low-crowned. Comparisons.—From M. p. drummondii (specimens from vicinity of Whitehorse, Y. T., Trutch, B. C., and Kinuso, Alberta), M. p. alcorni differs as follows: Averaging larger in all measurements taken except lengths of tail and hind foot, which are the same; color of upper parts slightly paler and more gray and less brown; underparts paler; zygomatic arches heavier, rounder and shorter; skull proportionately more massive, except the auditory bullae which are less inflated; maxillary teeth heavier and lower-crowned. From M. p. rubidus (specimens from Atlin, B. C.), M. p. alcorni differs as follows: Averaging larger in all cranial measurements taken except length of the maxillary tooth-row which is the same; color of upperparts more gray and less brown; underparts darker; skull longer with longer nasals and heavier zygomatic arches; skull of adult more heavily ridged. From M. p. admiraltiae (specimens from Admiralty Island), M. p. alcorni differs as follows: Averaging larger in all measurements taken; color of upper parts more gray and less brown, underparts darker. [Pg 105] [Pg 106] Remarks.—Microtus p. alcorni is a well-defined subspecies differing markedly from adjacent subspecies by a larger and heavier skull and broader, more rounded and heavier zygomatic arches. Characters examined in the specimens available are constant. Specimens from Haines are slightly darker than those from Kluane. An adult (No. 21534, UKMNH) from Northway has slightly more inflated auditory bullae than those from Kluane. An adult from Tyonek (No. 986, UKMNH) has richer brown upper parts. Measurements of this specimen resemble closely those of animals from Kluane, although the rostrum is noticably heavier. Several adults were available from many of the localities of occurrence of M. p. alcorni. At the locality 9 miles west and 4 miles north of Haines, there were four which were considered to be old adults. These four had larger measurements than others considered to be fully adult. In addition, the skulls were larger and more rugged. There were occasionally old adults in other series. For the sake of uniformity, I have not considered these aforementioned old adults in the comparative studies of younger adults. This subspecies is named in honor of J(oseph). R(aymond). Alcorn, the collector. Measurements.—Average and extreme measurements of six adults of both sexes of M. p. alcorni from the type locality are as follows: Total length, 162 (149-172); length of tail, 43 (39-45); condylobasal length, 26.3 (25.6-26.3); basal length, 25.2 (24.2-25.9); length of nasals, 7.3 (6.9-7.5); zygomatic breadth, 15.3 (14.9-15.6); breadth across auditory bullae, 12.8 (12.4- 13.2); alveolar length of upper molariform tooth-row, 6.4 (6.1-6.7). Seven adults of both sexes from 9 miles west and 4 miles north of Haines have the following measurements: 158 (148-165); 45 (41-50); 26.1 (25.5-26.8); 24.8 (24.4-25.7); 7.3 (7.0- 7.6); 14.9 (14.3-15.1); 12.2 (11.8-13.0); 6.2 (5.9-6.3). Specimens examined.—Total 65, distributed by localities of capture as follows and deposited in the University of Kansas Museum of Natural History: Alaska: E side Deadman Lake, 1800 ft., 15 mi. SE Northway, 7; 1 mi. NE Anchorage, 100 ft., 1; Tyonek, Cook's Inlet, 1; E side Chilkat River, 100 ft., 9 mi. W and 4 mi. N Haines, 37. Yukon Territory: 6 mi. SW Kluane, 2250 ft., 14; SW end Dezadeash Lake, 2; 1½ mi. S and 3 mi. E Dalton Post, 2500 ft., 3. Specimens reported by Osgood (1904:35) have not been seen by me but may be of this subspecies, and are tentatively referred to it. These are from the following localities in Alaska: Lake Clark near Keejik, near the mouth of the Chulitna River, and Kakhtul River near the junction with the Malchatna. Microtus pennsylvanicus tananaensis new subspecies Type.—Female, adult, skin with skull, No. 21509, Univ. Kansas, Mus. Nat. Hist., Yerrick Creek, 21 mi. W and 4 mi. N Tok Junction, Alaska; 20 July 1947; obtained by J. R. Alcorn; original No. 5023. Range.—East-central Alaska as far south as Tok Junction, as far west as Mt. McKinley, as far north as Fairbanks and as far east as Eagle. Diagnosis.—Size medium (see measurements); color of upper parts dark, near (n) Prout's Brown, with some individual variation; skull with zygomatic arches moderately heavy and wide; nasals relatively long; auditory bullae inflated. Comparisons.—From M. p. alcorni (see description), M. p. tananaensis differs as follows: Smaller in all measurements taken except alveolar length of upper molariform tooth-row which is the same; color of upper parts darker, more richly brown and less gray; underparts darker; zygomatic arches less massive and narrower; auditory bullae larger and more inflated. From M. p. drummondii (see comparisons under M. p. alcorni), M. p. tananaensis differs as follows: Larger in all cranial measurements taken except nasal length which is the same; color everywhere slightly darker; wider across zygomatic arches; zygoma thicker; nasals, relative to length of skull, shorter; auditory bullae larger and more inflated. Remarks.—For the most part the material available of this subspecies consisted of subadults; however, comparison of adults with those of adjacent subspecies indicates that this subspecies can be distinguished by color of the upper parts, cranial measurements, and size of the zygomatic arches and the auditory bullae. Specimens from 14 miles east and 25 miles north of Fairbanks are especially dark. One subadult (No. 21467, UKMNH) has blackish hair on the feet and a blackish unicolored tail. No. 241696, USBS, an old adult female, from Ketchumstock, is larger. The specimens referred to this subspecies, vary some in color, but vary less in cranial characters. Additional adults are needed from western Alaska to determine how far this subspecies extends down the valley of the Yukon River. Bailey (1900:24) lists one specimen from Nulato, as drummondii; I have not seen it but on geographic grounds tentatively assign it to M. p. tananaensis. Measurements.—Measurements of the type specimen are as follows: Total length, 160; length of tail, 40; condylobasal length, 26.0; basal length, 24.9; length of nasals, 6.7; zygomatic breadth, 14.5; breadth across auditory bullae, 12.5; alveolar length of upper molariform tooth-row, 6.2. Two specimens from Eagle (Nos. 128295 and 128320, USBS) have the following measurements respectively: 161, 154; 37.5, 36; 25.3, 25.4; 23.8, 23.9; 6.5, 6.8; 14.5, 14.6; 11.9, 12.3; 6.1, 6.1. Specimens examined.—Total 34, distributed by localities of capture as follows and unless otherwise stated in the University of Kansas Museum of Natural History: Alaska: Near Buster Creek, Chatanika River, 1 (USBS); Chatanika River, 700 ft., 14 mi. E and 25 mi. N Fairbanks, 4; Fairbanks, 2 (USBS); head of Glacier Creek, Mt. McKinley, 1 (USBS); Moose Creek, Mt. McKinley, 2 (USBS); head of Toklat River, 1 (USBS); Eagle, 4 (USBS); Yerrick Creek, 21 mi. W and 4 mi. N Tok Junction, 13; Ketchumstock, 2 (USBS); 9 mi. from mouth of Robertson River, 1 (USBS); Tanana, 3 (USBS); Tanana Crossing, 1 (USBS). Osgood (1909b:24) records specimens which may be of this subspecies from the following localities in Alaska: Charlie Creek, Circle, 20 miles above Circle, 40 miles above Circle, Nation Creek, and Seventy Mile Creek. Osgood (1900:36) also records specimens from near Fort Yukon. None of these has been seen by me; they are only tentatively assigned to this [Pg 107] [Pg 108] subspecies. Microtus pennsylvanicus drummondii (Audubon and Bachman) Arvicola drummondii Audubon and Bachman, Quadr. North Amer., 3:166, 1854. (Type, by subsequent designation, from vicinity of Jasper House, Alberta.) Microtus pennsylvanicus drummondii Hollister, Canadian Alp. Jour., Special Number, p. 23, February 17, 1913. Specimens examined.—Total 93, as follows: Yukon Territory: McIntyre Creek, 2250 ft., 3 mi. NW Whitehorse, 26; W side Lewes River, 2150 ft., 2 mi. S Whitehorse, 4; 5 mi. W Teslin River, 2400 ft., 16 mi. S and 53 mi. E Whitehorse, 7; E side Teslin River, 2300 ft., 16 mi. S and 59 mi. E Whitehorse, 1. British Columbia: 1 mi. NW jct. Irons Creek and Liard River, 8; Hot Springs, 3 mi. WNW jct. Trout River and Liard River, 3; N side Liard River, ½ mi. W jct. Liard River and Trout River, 1; ¼ mi. S jct. Trout River and Liard River, 13; S side Toad River, 10 mi. S and 21 mi. E Muncho Lake, 2; Summit Pass, 4200 ft., 10 mi. S and 70 mi. W Fort Nelson, 2; E side Minaker River, 1 mi. W Trutch, 19; Beatton River, 115 mi. S Fort Nelson, 1; 5 mi. W and 3 mi. N Fort St. John, 2. Alberta: Assineau River, 1920 ft., 10 mi. E and 1 mi. N Kinuso, 4. Remarks.—Adults among the specimens listed above vary but little; one female from Assineau River in Alberta is notably more reddish than others taken elsewhere. Average and extreme measurements of nine adults of both sexes of M. p. drummondii from E side Minaker River, 1 mi. W Trutch, British Columbia, are as follows: Total length, 157 (148-165); length of tail, 42 (37-46); condylobasal length, 25.1 (24.7-26.0); basal length, 24.2 (23.4-25.0); length of nasals, 6.8 (6.4-7.2); zygomatic breadth, 14.4 (13.9-14.7); breadth across auditory bullae, 12.4 (12.0-12.7); alveolar length of upper molariform tooth-row, 6.1 (6.0-6.2); Nine adults of both sexes from McIntyre Creek,...