_Specimens examined._--Total, 8: Morfield Canyon, 7600 ft., 75972,
75973; Upper Well, Prater Canyon, 7575 ft., 69235-69238; 1/4 mi. N
Middle Well, Prater Canyon, 7500 ft., 69239-69240.
The specimens from Prater Canyon were trapped in the grasses and sedges
of the meadow comprising the floor of the canyon. The ground and
vegetation were dry at the time of capture, September 2, 3, and 4, 1956.
_Microtus montanus_ was the only other species taken in the mouse traps
in the sedge and grass. Five of the six specimens from Prater Canyon are
young, having slightly worn teeth; the sixth is an old adult male the
teeth of which are so much worn that only a few traces of the
reddish-brown pigment remain. His testes were 5 mm. long. These
specimens are from an area of intergradation between _S. v. obscurus_
and _S. v. monticola_. The length of the maxillary tooth-row in these
six specimens averaged 6.23 (6.1-6.4) millimeters. Comparison with
average measurements of 6.6 and 6.8 in samples of _S. v. obscurus_, and
of 5.9 in a sample of _S. v. monticola_ (Findley, 1955:64, 65) reveals
the intermediate size of the specimens from the Mesa Verde. The gap
between habitat suitable for _Sorex vagrans_ on the Mesa Verde and the
nearest record-station for _S. v. monticola_ to the south and west in
the Chuska Mountains is wider than the gap between the Mesa Verde and
the nearest record-station for _S. v. obscurus_ to the north and east,
one mile west of Mancos, 75971, 7000 feet, or at Silverton. On
geographic grounds the specimens from the Mesa Verde are referred to _S.
v. obscurus_. The two specimens from Morfield Canyon were trapped on
November 4, 1957, and are grayish above and silvery below. Their pelage
contrasts markedly with the dorsally brownish and ventrally buffy pelage
of the September-taken specimens from Prater Canyon.