198 The Mammals of Colorado 
Putorius streatori leptiis Merriam, Proc. Biol. Soc. Wash., xvi., 
p. 76 (1903). 
Type locality. — Silverton, Colorado. 
Measurements. — Total length, 9.5; tail vert., 2.6; hind foot, 1.23. 
Description. — Summer pelage, from Merriam /. c, taken from 
a specimen from Alberta, Canada. Upper parts uniform drab 
brown (or between drab brown and hazel, but lacking the reddish 
of hazel); end of tail black; under parts white throughout, with 
straight line of demarcation along the sides, the white reaching 
down on under sides of legs to wrists and ankles; rest of legs and 
feet brown like back ; toes of fore feet white on upper side ; toes 
of hind feet mixed brown and white. A specimen taken in May, at 
Crested Butte, Gunnison County, in a pelage intermediate between 
winter and summer has the back a drab brown, without tinge 
of red ; a very different color from the brown of P. arizonensis . 
Winter pelage. White all over except the short black tip of the 
tail. 
The skull is, naturally, small and rather delicate, with marked 
postorbital constriction; postorbital processes moderately de- 
veloped; zygomata spreading but little, and somewhat arched; 
rostrum depressed ; bullae quite well inflated ; lambdoidal crests 
somewhat prominent; sagittal crest wanting or barely noticeable. 
The very small size of this weasel suffices to distinguish it from the 
other Colorado species. 
Distribution. — The Dwarf Weasel is seemingly distributed from 
Henry House, Alberta, Canada, south through the Rocky Mountains 
to Colorado, and probably into northern New Mexico. In Colorado 
it has been taken at Silverton, San Juan County ; in Larimer County; 
in Boulder County; at Crested Butte, Gunnison County; and at 
Coventry, Montrose County. It ranges high in the mountains, 
probably reaching, if not going above, timber-line. 
Habits. — I know nothing of special interest concerning 
the habits of this species. Probably from its small size it feeds 
largely on mice. In the mountains where the snow is deep 
in winter, one often sees the track of this animal disappear 
under the snow and then reappear a little farther on, the 
weasel having run through the light snow a little below the 
surface, very likely following the trail of some unlucky mouse. 
Genus LUTREOLA (diminutive of Intra, a httle otter) 
Liitreola Wagner Schreb., Saugth., Suppl. ii, p. 239 (1841). Type 
Alustela lutreola Linnaeus, 
