The diagnostic characters referred to in the original description of _Z. alleni_, as given earlier in this account, agree with characters of specimens of _Z. p. pacificus_. Howell (1920:233) remarks that, in coloration and length of foot, typical _alleni_ differs but slightly from _pacificus_. Howell (_loc. cit._) noted, as I also have, that there are slight cranial differences in specimens from various parts of the range of _Z. p. pacificus_; these variations are somewhat clinal in nature, cranial dimensions showing a slight increase from south to north. The largest animals occur in western Tehama, Trinity, and Siskiyou counties, California. Samples from various localities in Jackson County, Oregon, are slightly smaller than these, but are larger than specimens from the southern Sierra Nevada.
_Specimens examined._--Total, 264, distributed as follows:
CALIFORNIA: _Alpine County_: _Carson River, 1/4 mi. SW Woodfords, 5700 ft._, 3 (MVZ); _Diamond Valley, 5500 ft., 1 mi. SE Woodfords_, 6 (MVZ); _Faith Valley_, 1 (MVZ). _El Dorado County_: _Glen Alpine Creek, near Fallen Leaf Lake, 6600 ft._, 8 (MVZ); _1 mi. W Fyffe_, 1 (MVZ); _Fresno County_: _Hume_, 1 (MVZ). _Mariposa County_: _Chinquapin, 6700 ft., Yosemite Nat'l Park_, 12 (MVZ); _E fork Indian Canyon, 7300 ft._, 8 (MVZ); _Merced Grove, Big Trees_, 7 (MVZ); _1 mi. E Merced Lake_, 5 (MVZ); _near Mono Meadow, Yosemite Nat'l Park_, 4 (MVZ); _near Mt. Hoffman, 8100 ft., Yosemite Nat'l Park_, 5 (MVZ); _Porcupine Flat, 8100 ft., Yosemite Nat'l Park_, 9 (MVZ); _Yosemite Creek, Yosemite Valley_, 7 (MVZ); foot Yosemite Falls, Yosemite Nat'l Park, 8 (MVZ). _Mono County_: _Walker Lake, 8000 ft._, 5 (MVZ); _Swager Canyon, 7800 ft._, 3; Mono Lake P. O. 6500 ft., 4 (MVZ). _Placer Co._: Truckee River, Squaw Creek, 1 (SDM); _W bank Truckee River_, 1 (MVZ). _Plumas County_: Rich Gulch, 3850 ft., 11 mi. W and 8 mi. N Quincy, 2 (MVZ). _Shasta County_: Warner Creek, 8000 ft., Lassen Peak, 6 (MVZ). _Siskiyou Co._: _Donomore Meadow, 5800 ft., 15 mi. W Hilt_, 7 (MVZ); Poker Flat, 5000 ft., 12 mi. NW Happy Camp, 7 (MVZ); Little Shasta, 1 (USBS); Siskiyou Mts., 6000 ft., 2 (USBS); _Sisson_, 1 (SDM); _Mt. Shasta, 6500 ft._, 6 (MVZ). _Salmon River Divide_, 2 (MVZ); _S fork Salmon River, 5000 ft._, 7 (MVZ). _Tehama County_: _2 mi. W Black Butte, on Lassen Rd., 6800 ft._, 5 (MVZ); _2 mi. E Mineral, 5200 ft._, 2 (MVZ); 2 mi. S Yolla Bolly Mtn., 11 (MVZ). _Trinity Co._: _N fork Coffee Creek, 4500 ft._, 34 (MVZ); Canyon Creek, 4 (USBS); 8 mi. NE Hyampon, 2900 ft., 1 (MVZ); _3 mi. NNW Mad River Bridge, 2900 ft., South Fork Mtn._, 5 (MVZ); _1-1/2 mi. N Mad River Bridge, 3000 ft., South Fork Mtn._, 6 (MVZ); _1 mi. SW North Yolla Bolly Mtn._, 14 (11 MVZ); _1/2 mi. S South Yolla Bolly Mtn._, 3 (MVZ). _Tulare County_: _Jordan Hot Springs, Sierra Nevada Mts., 6700 ft._, 9 (MVZ); _Sherman Creek, Sequoia Nat'l Park_, 1 (MVZ); _Tokopah Valley, 7000 ft., Sequoia Nat'l Park_, 1 (MVZ); 2 mi. E Kern Peak, 9300 ft., Sierra Nevada Mts., 1 (MVZ). _Tuolumne County_: _head Lyle Canyon, Yosemite Nat'l Park, 10,000 ft._, 9 (MVZ); _Tuolumne Meadows, 8600 ft., Yosemite Nat'l Park_, 1 (MVZ).