TAYLOK — NEW MEADOW MOUSE FROM WASHINGTON 
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faint wash of huffy beneath. One specimen from Stehekin (no. 230,435, U. S. 
Nat. Mus., Biol. Surv. Coll.) is identical with the type in color above, but is 
more strongly washed below with light ochraceous-buff. 
Skull. — Compared with M. o. hairdi the crania are slightly longer, the rostra 
and nasals conspicuously so; incisor teeth tending to be longer and heavier, 
incisive foramina to be longer and narrower, particularly posteriorly, and zygo- 
mata slightly heavier. Compared with oregoni and hairdi, there are observable 
tendencies in cantwelli to larger size, longer rostra and nasals, and longer and 
narrower incisive foramina. The crania are very similar, however, and the 
differences at best are slight. 
Measurements. — Measurements of the type: Total length, 152; tail vertebrae, 
46; hind foot, 18; nasals, 7.8; zygomatic breadth, 14.8; alveolar length of upper 
molar series, 5.6. Average measurements of nine adults from different parts of 
the range of cantwelli, total length 150 mm. (max. 161, min. 138) ; tail vertebrae 
43 (max. 52, min. 34); hind foot, 18 (max. 19, min. 17); basal length, 21.9(max. 
23.4, min. 20.9); length of nasals, 7.0 (max. 7.3, min. 6.7); zygomatic breadth, 
14.3 (max. 14.9, min. 14.0); mastoid breadth, 11.4 (max. 12.6, min. 11.0); alveo- 
lar length of upper molar series, 5.7 (max. 6.1, min. 5.5). 
Specimens examined. — All are skins with skulls from the State of Washington. 
Mount Rainier, Glacier Basin, 5935 feet, 2; Mount Rainier, Sunset Park, 5000 
feet, 2; Mount Rainier, Reflection Lakes, 4900 feet, 1; Chelan County, Entiat 
River, 20 miles from mouth, 1680 feet, 4; Chelan County, Stehekin, head of Lake 
Chelan, 1079 feet, 9; Chelan County, Cascade Tunnel, 3373 feet, 3; Yakima 
County, Mt. Aix, head of Hindoo Creek, 6500 feet, 2; Yakima County, Goose 
Prairie, 3 miles northeast of Bumping Lake, 3300 feet, 1; Snohomish County, 
Chiwawa Mountain Fork of Suiattle River, 4500 feet, 1. 
Remarks. — The Chilotus stock, characteristic of the humid coast belt, 
has invaded the Cascade Mountains and, in places, penetrated to the 
east side. Apparently environment has effected a slight response in 
physical characteristics. 
Intergradation of Microtus oregoni cantwelli with the oregoni stock 
to the west and south is shown by specimens from Scenic (McCain), 
2106 feet, Snohomish County, and Signal Peak, 4000 feet, Yakima 
County. Examples from the west and south sides of Mount Rainier 
(from Sunset Park, 5000 feet, and Reflection Lakes, 4900 feet) referred 
to cantwelli, show characters tending toward oregoni. The extreme 
development of the subspecies has taken place in the higher country 
usually on the east slopes of the mountains, while specimens from 
lower altitudes, either east or west of the Cascade divide, possess less 
well-marked characters. Examples from lower levels of Mount Rainier 
National Park and nearby (Longmire Springs, 2700 feet; Mesler’s Ranch, 
2000 feet, one mile west of Park boundary) as well as specimens from 
Scenic (locality just given). Signal Peak (ditto), and Husum and Trout 
Lake, Klickitat County, are referred to oregoni. 
