RODENTIA-MURINAE-REITHRODON MONTANUS. 
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its root to the eye, or a little less than the head and body. It is well covered with short hairs, 
concealing the annuli. 
The colors of this animal are quite similar to those of the common house mouse; the back 
being of almost precisely the same shade of brown, perhaps a little darker. The under parts are 
grayish white tinged with reddish, but the lead-colored bases of the hairs, usually quite distinctly 
visible, impart a plumbeous aspect. The cheeks generally are fulvous, and in many specimens 
there is a distinct.band of the same on the lower part of the sides. The feet, region round the 
mouth, and chin, and under half of the tail are white, much more conspicuous in the alcoholic 
specimen than in the dried skin. 
Several specimens from St. Louis resemble this very closely, but are not in sufficiently good 
condition to be determined. 
The first published description of this species was by Audubon and Bachman in 1841. The 
Mus lecontii of the same authors appears to be very similar, except that the fulvous stripe on 
the sides is less distinct. As there is no difference except what might naturally result from 
age, I have reduced this name to a synonym. 
List of specimens. 
REITHRODON MONTANUS, Baird. 
Eeithrodon montanus, Baird, Pr. A. N. Sc. Phila. VII, April, 1855, 335. 
Sp. Ch. —Tail very little less than head and body, which barely exceed two inches. Hind foot. 50. Ears small, the 
membrane thickened, and with long coarse hairs. Above, brown and pale yellowish gray, much lighter than mouse color. 
Outside of ears and flanks, pale yellowish brown, without any rufous. Beneath, dull whitish. 
The single specimen of this species brought by Captain Beckwith appears quite adult, though 
of very diminutive size, that of a half grown mouse. The head is short and considerably 
arched, the muzzle hairy, except the septum and the inner edges of the nostrils, on which no 
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