_Diagnosis._--Size medium to small for the species; average and extreme measurements of 9 topotypes are: total length, 110.3 (105-117); tail, 46.4 (42-50); hind foot, 13.1 (12.5-13.5). Color grayish or brownish gray in summer, light grayish in winter.

_Comparisons._--For comparisons with _S. v. setosus_, _S. v.

longicauda_, _S. v. alascensis_ and _S. v. shumaginensis_ see accounts of those subspecies. Paler and slightly larger than S. v. soperi.

Larger than the subspecies from central Montana herein described as new. Smaller than _S. v. neomexica.n.u.s_. Averaging larger in all dimensions than _S. v. monticola_ with which _obscurus_ intergrades in northern New Mexico and northern Arizona. Larger than _S. v. vagrans_ with more grayish rather than reddish fresh summer pelage and light gray rather than dark grayish-black fresh winter pelage.

_Remarks._--Intergradation of _S. v. obscurus_ with _S. v. setosus_, _S. v. longicauda_, _S. v. alascensis_, and the new subspecies from Montana takes place in the usual way with specimens from intermediate localities being intermediate in size and color. However the relationship of _S. v. obscurus_ and _S. v. vagrans_ (as the latter subspecies is defined in this study) is rather complicated. In southern British Columbia where the two subspecies come together a situation of remarkable complexity prevails. Series from some localities seem to represent intergrades between _obscurus_ and _vagrans_; from other localities some specimens seem to be referable to one and some to the other subspecies; from other localities all specimens seem referable to one subspecies. A similar situation is seen in specimens from northeastern Washington, northern and central Idaho, and extreme western Montana. The region mentioned is one of extensive interfingering of life-zones. In southern British Columbia the main axes of the rivers, valleys and mountain ranges are north and south. Most of the valleys are in the Transition Life-zone; the forests are rather dry and of pine with more or less isolated hydrosere communities about streams and ponds. These hydrosere situations are the habitat of _Sorex vagrans_. Shrews from these situations are usually referable to _vagrans_. The high ridges and mountain ranges are usually in the Canadian Life-zone or higher and most of the shrews referable to _obscurus_ come from such places.

Marginal localities with regard to life-zone produce most of the populations which seem to represent intergrades between the two subspecies. Isolated areas of Canadian Life-zone, even though surrounded with Transition Life-zone, often harbor a population of _obscurus_, whereas the streams in the nearby dry valleys harbor populations of _vagrans_. Farther south in the Rocky Mountain chain, _obscurus_ seemingly intergrades regularly with _vagrans_. This intergradation is seen in populations from several localities in Utah.

There the lower elevations west of the Wasatch and Uinta mountains are inhabited by _S. v. vagrans_, the higher elevations by _obscurus_ and where the ranges of the two abut intergrading populations occur.

In these series of intergrades there are specimens which, using size as a subspecific criterion, would unhesitatingly be a.s.signed, as individuals, to _obscurus_, and others would be a.s.signed to _vagrans_, but these individuals represent extremes of a normally variable population. At Cuddy Mountain, Idaho, the two subspecies seemingly abut without intergradation; anyhow the available specimens from this locality are referable to one or the other subspecies and none is intermediate. The situation just described understandably has been the source of much anguish to students who sought to identify shrews from the Rocky Mountains. The reason for the relationship just described has been discussed at length in a previous section.

In the Rocky Mountains of Wyoming and Colorado the subspecies _S. v.

obscurus_ ranges almost uninterruptedly over relatively large areas, but southward in New Mexico and southwestward into Utah and Arizona, suitable boreal habitat becomes insular in nature and obscurus there is confined to the higher mountains. With one exception, once the shrew populations become 'insular' in this region they become smaller and show intergradation with _Sorex vagrans monticola_. The exception is the population in the Sacramento Mountains of southeastern New Mexico which is larger than _obscurus_ and has been rightly recognized as a distinct subspecies, _neomexica.n.u.s_.

Almost without exception the range of typical _Sorex vagrans obscurus_ is sympatric with that of _Sorex cinereus_, usually the subspecies _S.

c. cinereus_. So close is this correspondence that the presence of _S.

cinereus_ comes near to being a useful aid in identifying _S. v.

obscurus_. In areas where individuals of _obscurus_ show intergradation with _vagrans_, _Sorex cinereus_ is absent or rare. The implication is that as the species _S. vagrans_ approaches the size of the species S. cinereus, compet.i.tion between the two increases with resultant displacement of _cinereus_.

_Specimens examined._--Total number, 982.

ALASKA: Wahoo Lake, 69 08' N, 146 58' W, 2350 ft., 2 KU; Chandler Lake, 68 12' N, 152 45' W, 2900 ft., 1 KU; Bettles, 1 KU, 5 BS; Alatna, 1 BS; Yukon River, 20 mi. above Circle, 1 BS; Tanana, 1 BS; Mountains near Eagle, 18 BS; Richardson, 8 BS; head of Toklat River, 11 BS; Savage River, 8 BS.

YUKON: MacMillan Pa.s.s, Mile 282, Canol Road, 1 NMC; MacMillan River, Mile 249, Canol Road, 1 NMC; S. fork MacMillan River, Mile 249, Canol Road, 2 NMC; Sheldon Lake, Mile 222, Canol Road, 5 NMC; Rose River, Mile 95, Canol Road, 1 NMC; McIntyre Creek, 3 mi. NW Whitehorse, 2250 ft. 1 KU; Nisutlin River, Mile 40, Canol Road, 6 NMC; SW end Dezadeash Lake, 2 KU; 3 mi. E and 1-1/2 mi. S Dalton Post, 2500 ft., 1 KU.

MACKENZIE: Nahanni River Mtns., Mackenzie River, 1 BS; Fort Simpson, 3 BS; Fort Resolution, Mission Island, 1 BS.

BRITISH COLUMBIA: W. side Mt. Glave, 4000 ft., 14 mi. S and 2 mi. E Kelsall Lake, 1 KU; Stonehouse Creek, 5-1/2 mi. W jct. Stonehouse Creek and Kelsall River, 4 KU; Bennett City, 6 BS; Wilson Creek, Atlin, 1 PMBC; McDame Post, Dease River, 6 BS; McDame Creek, 3 BS; Hot Springs, 3 mi. WNW jct. Trout River and Liard River, 1 KU; NW side Muncho Lake, 1 KU; Little Tahtlan River, 1 AMNH; Junction (4 mi. N Telegraph Creek), 7 BS; Raspberry Creek, 16 AMNH; Klappan River Valley, 1 BS; Chapa-atan River, 4 BS; Fort Grahame, 3 BS; Kispiox Valley, 23 mi. N Hazleton, 1 BS; Bear Lake, site of Fort Connully, 2 BS; Tetana Lake, 1 PMBC; Hudson Hope, 2 BS; Charlie Lake, 3 PMBC; Babine Mts., 6 mi. N Babine Trail, 5200 ft., 1 BS; Big Salmon River (S branch near Canyon), 1 BS; Ootsa Lake, 2 PMBC; Indianpoint Lake, 4 PMBC; Barkerville, 7 BS; Yellowhead Lake, 2 NMC, 1 PMBC; N. fork Moose River, 1 BS; Moose Lake, 2 BS; Moose Pa.s.s, 1 BS; Glacier, 7 AMNH, 12 BS; Golden, 1 BS; Field, 2 BS; Caribou Lake, near Kamloops, 2 BS; Sicamous, 1 BS; Monashee Pa.s.s, 4 PMBC; Paradise Mine, 3 PMBC; Level Mtn., 4 AMNH; 6 mi. S Nelson, 6 BS; Morrissey, 5 NMC; Wall Lake, 1 BS.

ALBERTA: Hays Camp, Slave River, Wood Buffalo Park, 1 NMC; Kinuso, a.s.sineau River, 1920 ft., 2 KU; Athabaska River, 30 mi. above Athabaska Landing, 8 BS; Smokey Valley, 50 mi. N Jasper House, 1 BS; Sulfur Prairie, Grande Cache River, 3 BS; Stoney River, 35 mi. N Jasper House, 1 BS; Moose Mtn., 1 NMC; Rodent Valley, 25 mi. W Henry House, 1 BS; Henry House, 3 BS; Jasper, 2 NMC; Shovel Pa.s.s, 4 NMC; mouth of Cavell Creek, Jasper Park, 1 NMC; 11 mi. S Henry House, 2 BS; 15 mi. S Henry House, 1 BS; Red Deer River, 1 AMNH; 27 mi. W Banff, 3 NMC; 12 mi. WNW Banff, 4500 ft., 1 NMC; N. Fork Saskatchewan River, 5000 ft., 1 NMC; Cypress Hills, 1 NMC; Waterton Lakes Park, 53 NMC.

SASKATCHEWAN: Cypress Hills, 21 NMC.

WASHINGTON: _Okanogan Co._: Pasayten River, 1 BS; Bauerman Ridge, 1 BS; Conconully, 2 BS. _Pend Oreille Co._: 2 mi. N Gypsy Meadows, 2 WSC; Round Top Mtn., 1 WSC; head Pa.s.s Creek, 1. _Chelan Co._: Stehekin, 4 BS; head Lake Chelan, 4 BS; Wenatchee, 1 BS. _Kitt.i.tas Co._: Easton, 10 BS.

IDAHO: _Boundary Co._: Cabinet Mtns., E Priest Lake, 2 BS. _Adams Co._: 1/2 mi. E Black Lake, 1 KU; 1 mi. N Bear Creek R. S., SW slope Smith Mtn., 2 KU. _Washington Co._: 1 mi. NE Heath, SW slope Cuddy Mtn., 4000 ft., 4 KU. _Lemhi Co._: 10 mi. SSW Leadore (type locality), 4 BS; 5 FC. _Fremont Co._: 7 mi. W West Yellowstone, 4 KU. _Custer Co._: head Pahsimeroi River, Pahsimeroi Mtns., 1 BS. _Blaine Co._: Perkins Lake, 1 KU. _Bear Lake Co._:--_Caribou Co._ line: Preuss Mts., 1 BS.

MONTANA: _Glacier Co._: Sherburne Lake, 3 UM; 2-1/2 mi. W and 1-1/2 mi. S Babb, 1 KU; St. Mary's, 6 UM; St. Mary Lakes, 9 BS; Fish Creek, 2 BS; Gunsight Lake, 2 BS. _Flathead Co._: Nyack, 3 UM, 1 BS; 1 mi. W and 2 mi. S Summit, 1 KU. _Ravalli Co._: 8 mi. NE Stevensville, 3 BS; Sula, 1 BS. _Meagher Co._: Big Belt Mtns., Camas Creek, 4 mi. S Fort Logan, 7 BS. _Gallatin Co._: West Gallatin River, 4 BS. _Park Co._: Emmigrant Gulch, 3 mi. SE Chico, 2 BS; Beartooth Mtns., 2 BS; _Carbon Co._: Pryor Mtns., 2 BS.

WYOMING: _Yellowstone Nat'l Park_: Mammoth Hot Springs, 11 BS; Tower Falls, 1 BS; Astringent Creek, 1 BS; Flat Mtn., 1 BS; Yellowstone Park, 1 UM. _Park Co._: Beartooth Lake, 15 BS; SW slope Whirlwind Peak, 1 KU; Pahaska Tepee, 6300 ft., 8 BS; Pahaska, mouth Grinnell Creek, 15 BS; Pahaska, Grinnell Creek, 7000-7500 ft., 18 BS; 25 mi. S and 28 mi. W Cody, 1 KU; Valley, Absaroka Mts., 14 BS; Needle Mtn., 2 BS. _Big Horn Co._: 28 mi. E Lovell, 9000 ft., 12 KU; head Trapper's Creek, W slope Bighorn Mtns., 7 BS; 17-1/2 mi. E and 4-1/2 mi. S Sh.e.l.l, 1 KU. _Teton Co._: Two Ocean Lake, 6 FC; Emma Matilda Lake, 2 BS; 1 mi.

N Moran, 1 FC; 2-1/2 mi. E and 1/4 mi. N Moran, 6230 ft., 2 KU; Moran, 7 FC, 1 KU; 2-1/2 mi. E Moran, 6220 ft., 1 KU; 1 mi. S Moran, 1 FC; 3-3/4 mi.

E and 1 mi. S Moran, 9 KU; 7 mi. S Moran, 3 FC; Timbered Island, 14 mi. N Moose, 6750 ft., 3 KU; Bar BC Ranch, 2-1/2 mi. NE Moose, 6500 ft., 1 KU; Beaver d.i.c.k Lake, 1 UM; Teton Mtns., Moose Creek, 6800 ft., 9 BS; Teton Mtns., S Moose Creek, 10,000 ft., 3 BS; Teton Pa.s.s, above Fish Creek, 7200 ft., 15 BS; Whetstone Creek, 4 UM; Flat Creek-Gravel Creek Divide, 2 UM; Flat Creek-Granite Creek Divide, 1 UM; Jackson, 3 KU, 2 UM. _Fremont Co._: Togwotee Pa.s.s, 5 FC; Jackey's Creek, 3 mi. S Dubois, 1 BS; Milford, 5400 ft., 2 KU; Mosquito Park R. S. 17-1/2 mi. W and 2-1/2 mi. N Lander, 1 KU; 17 mi. S and 6-1/2 mi. W Lander, 9300 ft., 1 KU; Moca.s.sin Lake, 19 mi. W and 4 mi. N Lander, 10,000 ft., 1 KU; 23-1/2 mi. S and 5 mi. W Lander, 8600 ft., 1 KU; Green Mts., 8 mi. E Rongis, 8000 ft., 4 BS. _Washakie Co._: 9 mi. E and 5 mi. N Tensleep, 7400 ft., 2 KU; 9 mi. E and 4 mi. N Tensleep, 7000 ft., 2 KU. _Lincoln Co._: Salt River Mtns., 10 mi. SE Afton, 5 BS; Labarge Creek, 9000 ft., 1 BS. _Sublette Co._: 31 mi. N Pinedale, 8025 ft., 3 KU; Surveyor's Park, 12 mi. NE Pinedale, 8000 ft., 2 BS; N. side Half Moon Lake, 7900 ft., 1 KU; 2-1/2 mi. NE Pinedale, 7500 ft., 2 KU. _Natrona Co._: Rattlesnake Mts., 7000-7500 ft., 18 BS; Casper Mts., 7 mi. S Casper, 6 BS. _Converse Co._: 21-1/2 mi. S and 24-1/2 mi. W Douglas, 7600 ft., 7 KU; 22 mi. S and 24-1/2 mi. W Douglas, 7600 ft., 4 KU; 22-1/2 mi. S and 24-1/2 mi. W Douglas, 7600 ft., 2 KU. _Uinta Co._: 1 mi. N Fort Bridger, 6650 ft., 1 KU; Fort Bridger, 3 KU; Evanston, 1 BS; 9 mi. S Robertson, 8000 ft., 6 KU; 9 mi. S and 2-1/2 mi. E Robertson, 8600 ft., 1 KU; 10 mi. S and 1 mi. W Robertson, 8700 ft., 3 KU; 10-1/2 mi. S and 2 mi. E Robertson, 8900 ft., 1 KU; 13 mi. S and 1 mi. E Robertson, 9000 ft., 1 KU; 13 mi. S and 2 mi E Robertson, 9200 ft., 1 KU. _Carbon Co._: Ferris Mts., 7800 to 8500 ft., 13 BS; Shirley Mts., 7600 ft., 7 BS; Bridget's Pa.s.s, 18 mi. SW Rawlins, 7500 ft., 2 KU; 10 mi. N and 12 mi. E Encampment, 7200 ft., 1 KU; 10 mi. N and 14 mi. E Encampment, 8000 ft., 6 KU; 9-1/2 mi. N and 11-1/2 mi. E Encampment, 7200 ft., 2 KU; 9 mi. N and 3 mi. E Encampment, 6500 ft., 1 KU; 9 mi. N and 8 mi. E Encampment, 7000 ft., 1 KU; 8 mi. N and 14 mi. E Encampment, 8400 ft., 3 KU; 8 mi. N and 14-1/2 mi. E Encampment, 8100 ft., 2 KU; 8 mi. N and 16 mi. E Encampment, 4 KU; 8 mi. N and 21-1/2 mi. E Encampment, 9400 ft., 2 KU; S. base Bridger's Peak, 8800 ft., Sierra Madre Mts., 3 BS; 8 mi. N and 19-1/2 mi. E Savery, 8800 ft., 2 KU; 7 mi. N and 17 mi. E Savery, 8300 ft., 1 KU; 6-1/2 mi. N and 16 mi. E Savery, 8300 ft., 1 KU; 6 mi. N and 15 mi. E Savery, 8500 ft., 1 KU; 5 mi. N and 10-1/2 mi. E Savery, 8000 ft., 2 KU; 14 mi. E and 6 mi. S Saratoga, 8800 ft., 1 KU. _Albany Co._: Springhill, 12 mi. N Laramie Peak, 6300 ft., 10 BS; Laramie Peak, N. slope, 8000 to 8800 ft., 7 BS; Bear Creek, 3 mi. SW Laramie Peak, 7500 ft., 6 BS; 2-1/2 mi. ESE Brown's Peak, 10,500 ft., 2 KU; 3 mi.

ESE Brown's Peak, 10,000 ft., 1 KU; 27 mi. N and 5 mi. E Laramie, 6960 ft., 2 KU; 1 mi. SSE Pole Mtn., 8350 ft., 3 KU; 2 mi. SW Pole Mtn., 3 KU; 3 mi. S Pole Mtn., 8100 ft., 2 KU; 8-3/4, mi. E and 6-1/2 mi.

S Laramie, 8200 ft., 2 KU; Woods P. O., 1 BS. _Laramie Co._: 5 mi.

W and 1 mi. N Horse Creek P. O., 7200 ft., 2 KU.

UTAH: _Weber Co._: Mt. Willard, Weber-Box Elder Co. line, 9768 ft., 2 UU. _Salt Lake Co._: b.u.t.terfield Canyon, 7000 ft., 1 UU; Brighton, Silver Lake P. O., 8700 ft., 2 UU; Brighton, Silver Lake P. O., 8750 ft., 8 UU; Brighton, Silver Lake P. O., 9000 ft., 2 UU; Brighton, Silver Lake P. O., 9500 ft., 1 UU. _Summit Co._: Jct. Bear River and East Fork, 2 CM; Smith and Morehouse Canyon, 7000 ft., 1 UU; Mirror Lake, 10,000 ft., 1 UU. _Daggett Co._: Jct. Deep and Carter creeks, 7900 ft., 1 UU. _Utah Co._: Nebo Mtn., 1 mi. E Payson Lake, 8300 ft., 1 UU; Nebo Mts., 12 mi. SE Payson Lake, 1 UU. _Wasatch Co._: Current Creek, Uinta Mts., 1 BS; Wasatch Mts., 1 BS. _Uintah Co._: Paradise Park, 21 mi. W and 15 mi. N Vernal, Uinta Mts., 10,050 ft., 2 CM, 3 KU; Paradise Park, Uinta Mts., 10,100 ft., 6 UU. _Sanpete Co._: Manti, 3 BS. _Sevier Co._: 7 mi. Creek, 20 mi. SE Salina, 5 CM; Fish Lake Plateau, 2 BS. _Emery Co._: Lake Creek, 11 mi. E Mt. Pleasant, 4 CM.

_Grand Co._: Warner R. S., La Sal Mts., 9750 ft., 2 UU; La Sal Mts., 11,000 ft., 1 BS. _Beaver Co._: Puffer Lake, Beaver Mts., 2 BS. _Wayne Co._: Elkhorn G. S., Fish Lake Plateau, 14 mi. N Torrey, 9400 ft., 3 UU. _Garfield Co._: Wildcat R. S., Boulder Mtn., 8700 ft., 6 UU; 18 mi. N Escalante, 9500 ft., 1 UU. _Washington Co._: Pine Valley Mts., 7 BS. _San Juan Co._: Geyer Pa.s.s, 18 mi. SSE Moab, 3 CM; Cooley, 8 mi. W Monticello, 3 CM.

COLORADO: _Larimer Co._: Poudre River, 1 KU. _Rio Blanco Co._: 9-1/2 mi.

SW PaG.o.da Peak, 2 KU. _Grand Co._: Arapaho Pa.s.s, Rabbit Ears Mts., 2 BS. _Boulder Co._: Willow Park, Rocky Mtn. Nat'l Park, 8 UM; Longs Peak, 1 BS; 3/4 mi. N and 2 mi. W Allenspark, 8400 ft., 5 KU; Ward, 9500 ft., 1 BS; Buchanan Pa.s.s, 1 BS; 3 mi. S Ward, 1 KU; 7 mi. NW Nederland, 1 KU; 5 mi. W Boulder, 3 BS; Boulder, 3 BS, 1 ChM; Nederland, 6 BS, 4 ChM; Eldora, 1 BS. _Garfield Co._: Baxter Pa.s.s, 8500 ft., 2 BS. _Eagle Co._: Gores Range, 1 BS. _Gilpen Co._: Black Hawk, 1 BS. _Lake Co._: 3 mi. W Twin Lakes, 2 KU; 12 mi. S and 1 mi. W Leadville, 1 KU. _Gunnison Co._: 2 mi. W Gothic, 2 FC; Copper Lake, 2 FC; Gothic, 1 FC. _Chaffee Co._: St. Elmo, 10,100 ft., 2 BS; E side Monarch Pa.s.s, 7 mi. W Salida, 2 ChM. _Teller Co._: Glen Core, Pikes Peak, 2 UM. _El Paso Co._: Hunters Creek, a tributary of Bear Creek, 7250-7400 ft., 1 AMNH. _Montrose Co._: Uncomphagre Plateau, 8500 ft., 3 BS. _Saguache Co._: 3 mi. N and 16 mi. W Saguache, 8500 ft., 2 KU; Cochetopa Pa.s.s, 10,000 ft., 4 KU; Monshower Meadows, 27 mi. W Saguache, 2 BS. _San Juan Co._: Silverton, 4 BS. _Mineral Co._: 23 mi.

S and 11 mi. E Creede, 1 KU. _Costilla Co._: Fort Garland, 2 BS.

_Huerfano Co._: 5 mi. S and 1 mi. W Cuchara Camps, 8 KU.

NEW MEXICO: _Taos Co._: 3 mi. N Red River, 2 BS; Taos, 1 BS. _Colfax Co._: 1 mi. S and 2 mi. E Eagle Nest, 8100 ft., 2 KU. _Sandoval Co._: Jemez Mts., 3 BS. _Santa Fe Co._: Hyde Park, 5 mi. NE Santa Fe, 2 HC; Santa Fe Field Station, 1 HC; Santa Fe Ski Basin, 1 KU; Pecos Baldy, 4 BS. _Torrance Co._: Manzano Mts., 2 BS.

_Marginal Records._--ALASKA: Chandler Lake, 68 12' N, 152 45' W; Yukon River, 20 mi. above Circle; Mountains near Eagle. MACKENZIE: Nahanni River Mts.; Fort Simpson; Fort Resolution, Mission Island. ALBERTA: Wood Buffalo Park; Athabaska River, 30 mi. above Athabaska Landing.

SASKATCHEWAN: Cypress Hills. MONTANA: St. Mary; 4 mi. S Fort Logan; Pryor Mts. WYOMING: 1 mi. W and 1 mi. S Buffalo, 27424 KU; Springhill, 12 mi. N Laramie Peak; 5 mi. W and 1 mi. N Horse Creek PO. COLORADO: Boulder; Hunters Creek; 5 mi. S and 1 mi. W Cuchara Camps. NEW MEXICO: 3 mi. N Red River, 10,700 ft.; Pecos Baldy; Manzano Mts.; Jemez Mts.

COLORADO: Navajo River (Jackson, 1928:120); Silverton. UTAH: La Sal Mts., 11,000 ft. COLORADO: Baxter Pa.s.s. UTAH: junction Trout and Ashley Creeks, 9700 ft. (Durrant, 1952:35); Mirror Lake, 10,000 ft.; Mt. Baldy R. S. (Durrant, 1952:53); Wildcat R. S.; Pine Valley Mts.; Puffer Lake; b.u.t.terfield Canyon. IDAHO: Preuss Mts.; 4 mi. S Trude (Davis, 1939:104); head Pahsimeroi River, Pahsimeroi Mts.; Perkins Lake; 1 mi. NE Heath; _1/2 mi. E Black Lake_. MONTANA: Sula; 8 mi. NE Stevensville. WASHINGTON: head Pa.s.s Creek; Conconully; Wenatchee; Easton; Stehekin; Pasayten River. BRITISH COLUMBIA: Second Summit, Skagit River, 5000 ft., (Jackson, 1928:120); Babine Mts., 6 mi. N Babine Trail, 5200 ft.; Hazleton (Jackson, 1928:120); 23 mi. N Hazleton; Flood Glacier, Stikine River (Jackson, 1928:120); Cheonee Mts. (_ibid._); Level Mtn.; west side Mt. Glave, 4000 ft., 14 mi. S and 2 mi. E Kelsall Lake. ALASKA: head Toklat River; Tanana; Alatna; Bettles.

=Sorex vagrans soperi= Anderson and Rand

_Sorex obscurus soperi_ Anderson and Rand, Canadian Field-Nat., 59:47, October 16, 1945.

_Type._--Adult male, skin and skull; No. 18249, Nat. Mus. Canada; obtained on September 21, 1940, by J. Dewey Soper, from 2-1/2 mi. NW Lake Audy, Riding Mtn. Nat'l Park, Manitoba.

_Range._--Southwestern Manitoba to central Saskatchewan.

_Diagnosis._--Size medium to small for the species; measurements of type and two topotypes are: total length, 107, 108, 117; tail, 45, 45, 45; hind foot, 12.1, 12.3, 12.5. Color dark brownish or fuscous in summer pelage; winter pelage unknown.

_Comparison._--Resembles _S. v. obscurus_ in size; darker than _obscurus_ in summer pelage; cranium slightly higher and top more nearly flat; larger and darker in summer pelage than the new subspecies from central Montana.

_Remarks._--In their description of this subspecies Anderson and Rand pointed out that specimens from the type locality and from central Saskatchewan represent the dark extreme in a color cline which begins in south-central British Columbia with "pale, brownish-tinged animals." These authors referred shrews from Cypress Hills, southwestern Saskatchewan and southeastern Alberta to _S. o. soperi_, although they noted that these specimens, taken by themselves, are not strikingly different from _S. o. obscurus_ from the Rocky Mountains.

The specimens from the Cypress Hills were included in _soperi_ because the authors felt that the subspecific boundary should be drawn "where specimens average about half way between the extremes (of the cline) in characters."

It is true, as Anderson and Rand say, that the shrews from Cypress Hills are hardly separable from those from, say, Waterton Lakes Park.

The specimens from the Cypress Hills are noticeably different from specimens from the Okanagan area, but some of the latter, in my opinion may represent intergrades between _S. v. obscurus_ and the more reddish _S. v. vagrans_ and are not, at any rate, typical _obscurus_. In view of the similarity of shrews from Cypress Hills to typical _S. v. obscurus_ and since the Cypress Hills are much nearer to the range of _S. v. obscurus_ than to the record-stations of occurrence in central Saskatchewan and Manitoba, I have chosen to restrict the name _soperi_ to shrews from these latter two localities.

Seemingly _S. vagrans_ is absent from the plains separating the Cypress Hills from the Rocky Mountains and from Riding Mountain National Park.

_Specimens examined._--none.

_Marginal records._--SASKATCHEWAN: Prince Albert National Park, 1700 ft. (Anderson and Rand, 1945:48). MANITOBA: Riding Mountain National Park, 2-1/2 mi. NW Audy Lake (ibid.).

=Sorex vagrans longiquus= new subspecies

_Type._--First year male, skin and skull; No. 87332, Univ. Michigan Mus. Zool.; obtained on July 21, 1942, by Emmet T. Hooper from 25 mi.

ESE Big Sandy, Eagle Creek, Chouteau Co., Montana, original no. 2184.

_Range._--Central Montana; marginal localities are: Bearpaw Mts., Zortman, Big Snowy Mts., Buffalo, Little Belt Mts.

_Diagnosis._--Size small for the species; measurements of three topotypes are: total length, 101, 105, 108; tail, 39, 40, 42; hind foot, 11.5, 11.5, 12. Color pale; summer pelage: back near (17"'_k_) Olive Brown but hairs of dorsum with a pale, buffy band proximal from the tips which imparts a pale over-all appearance; flanks near Wood Brown; underparts Pale Smoke Gray, usually not with a buffy wash; color of underparts often extending along margin of upper lip. Skull small for species; rostrum relatively broad and heavy; relatively broad interorbitally.

_Comparisons._--From _S. v. obscurus_, _S. v. longiquus_ differs as follows: size smaller; skull smaller in all dimensions although similar in proportion. From _S. v. soperi_, _S. v. longiquus_ differs in: size smaller; color paler in summer pelage. From _S. v. vagrans_, _S. v. longiquus_ differs in: color paler in summer pelage, less brownish; color of venter extending higher on flanks; venter Pale Smoke Gray, rarely tinged with buffy rather than usually tinged with buffy. From _S. v. monticola_, _S. v. longiquus_ differs in: summer pelage slightly paler, venter Pale Smoke Gray rather than suffused with buffy.

_Remarks._--The subspecies _longiquus_ is obviously derived from the neighboring _S. v. obscurus_ and differs from it mainly in size. Some specimens of obscurus from western Montana show evidences of intergradation with _S. v. vagrans_ in possessing a somewhat buffy belly and these are thus more strikingly different from _longiquus_ than are other specimens of _obscurus_. Many specimens of _obscurus_ from the eastern slope of the Lewis and Clark Range in Montana show the tricolored pattern seen in many specimens of _longiquus_. The smallest individuals of longiquus are found on the Big Snowy Mountains. Intergradation with _obscurus_ is seen in specimens here referred to _S. v. obscurus_ from the Big Belt Mountains.

_Specimens examined._--Total number, 45. MONTANA: _Hill Co._: Bearpaw Mts., 5 UM, 2 BS. _Phillips Co._: Zortman, 1 BS. _Chouteau Co._: type locality, 3 UM; Highwood Mts., 13 BS. _Cascade Co._: Neihart, Little Belt Mts., 1 BS. _Judith Basin Co._: 3 mi. W Geyser, 4100 ft., 1 KU; Otter Creek, 10 mi. SW Geyser, 1 BS; Dry Wolf Creek, 20 mi. SW Stanford, 1 BS. Buffalo, 13 mi. W Buffalo Canyon, 2 BS. _Fergus Co._: Moccasin Mts., 15 mi. NW Hilger, 3 BS; Judith Mts., 17 mi. NE Lewiston, 1 BS; 15 mi. S Heath, N. fork Flat Willow Creek, Big Snowy Mts., 1 BS; Timber Creek, Big Snowy Mts., 1 BS; Crystal Lake, 6000 ft., Big Snowy Mts., 2 UM; Rocky Creek, 5600 ft., Big Snowy Mts., 3 UM; Big Snowy Mts., 3 BS. _Meagher Co._: Sheep Creek, 16 mi. N White Sulphur Springs, Little Belt Mts., 1 BS.