6; _16 mi. W Loveland, 6840 ft._, 1; 6 mi. W,
1/2 mi. S Loveland, 5200 ft., 1. _Rio Blanco Co._: Meeker, 1
(USBS); _9-1/2 mi. SW Pagoda Peak_, 7700 ft., 3; 5 mi. S Pagoda
Peak, 9100 ft., 2. _Eagle Co._: Eagle, 1 (USBS); Pando, 2 (USBS).
_Grand Co._: Mt. Whiteley, 2 (USBS); Arapahoe Pass, Rabbit Ear
Mountains, 2 (USBS); Coulter (near Granby), 5 (USBS); _Arrowhead_
(near Dale), 1 (USBS). _Boulder Co._: 3/4 mi. N, 2 mi. W
Allenspark, 8400 ft., 4; _3 mi. S Ward_, 9000 ft., 3; Nederland, 16
(Chi). _Clear Creek Co._: Mt. McLellan, 2 (USBS); Berthoud Pass, 4.
_Park Co._: Trout Creek Ranch, 2 mi. N Garo, 1 (USBS).

Specimens examined of _M. m. nanus_ from eastern Idaho and Montana
are as follows: IDAHO: _Custer Co._: Challis, 7 (USBS); Mill Creek,
Challis Nat. Forest, 1 (USBS); Pahsimeroi Mts., 12 (USBS); Lost
River Mts., 1 (USBS). _Fremont Co._: N fork Snake River, 10 mi. SW
Island Park, 6200 ft., 2 (AMNH); Black Springs Creek, 4 mi. W
Ashton, 5200 ft., 1 (AMNH); 5 mi. W St. Anthony, 5000 ft., 1
(AMNH). _Camas Co._: Camas Prairie, Corral, 5100 ft., 2 (USBS).
_Blaine Co._: Alturas Lake, 3 (USBS); _Sawtooth Lake_, 2 (USBS);
Craters of the Moon, Laidlow Park, 2 (Mich); Ticura, 10 mi. S
Picabo, 1 (USBS); 19 mi. NE Carey (Lava Lake), 8 (Mich). _Butte
Co._: _26 mi. SW Arco_, 12 (Mich). _Bingham Co._: Shelley, 6
(USBS). _Bonneville Co._: 10 mi. SE Irwin, 4 (USBS). _Owyhee Co._:
Three Creeks, 3 (USBS). _Twin Falls Co._: Castleford Fenced Plot,
11 mi. W, 9 mi. S Twin Falls, 1. _Minidoka Co._: _Heyburn_, 2
(USBS). _Cassia Co._: 2 mi. S, 2 mi. W Burley, 5. _Bannock Co._:
Pocatello, 23 (USBS 4); Swan Lake, 1 (USBS). _Bear Lake Co._:
Montpelier Creek, 6700 ft., 3 (USBS). MONTANA: _Gallatin Co._: W.
Fork of W. Fork, Gallatin River, 1 (USBS). _Park Co._: Lamar River,
7000 ft., 1 (USBS); Gardiner, 1 (USBS). _Sweet Grass Co._: 14 mi. S
Big Timber, 1 (USBS); _McLeod_, 1 (USBS); West Boulder Creek, 18
mi. SE Livingston, 2 (USBS).

=Microtus montanus codiensis=, new subspecies

_Type._--Female, adult, skin and skull; No. 27578, Museum of
Natural History, University of Kansas, from 3-1/5 mi. E and 3/5 mi.
S Cody, 5020 ft., Park Co., Wyoming; obtained on August 11, 1948,
by James W. Bee, original number 18-8-11-48.

_Range._--In northwestern Wyoming eastward from the Absa