124 MONOGRAPHS OF NORTH AMERICAN RODENTIA. 
Hesperomys lecontii, WAGNER, Wieg. Arch. 1843, pt. ii, 51 (after Aud. & Bach.). 
Reithrodon lecontii, LECONTE, Proc. Acad. Nat. Sci. Phila. vi, 1853, 413. 
? Mus carolinensis, AUD. & Bacu., Journ. Acad. Nat. Sei. Phila. viii, pt. ii, 1842, 306; Q. N. A. iii, 1854, 332. 
(South Carolina, in inundated lands, rare. “Tail longer than the body, ears long and hairy, 
color light plumbeous; * * under surface scarcely a shade lighter. Length of head an? 
body 2.33, of tail 2.75, ear 0.33, tarsus 0.54.”) 
? Hesperomys carolinensis, WAGNER, Wieg. Arch. 1843, pt. ii, 51 (a‘ter Aud. & Bach.). 
? Pcithrodon carolinensis, BarrD, M.N. A. 1857, 452 (after Aud. & Bach.). 
Reithrodon megalotis, Barrp, M. N. A. 1857, 451; Rep. U. S. and Mex. Bound. Surv. ii, pt. ii, 1859, Mam- 
mals, 43, pl. vii, fig. 4a-c, and pl. xxiv, fig. da-g. (Sonorae Largest of North American 
species. Head and body, 24-3; tail, 24; sole, 4-3; ear, 0.43 high. Colors as in R. humile.) 
Dracnosis.—O. mure musculo minor seu staturd subequans, caudd trun- 
cum subequante hirsuta, sub-bicolore, auriculis prominulis, hirsutis, plantis 
semi-nudis, vellere molli, supra murino, infra griseo-albido, lateribus fulves- 
centibus. : 
Hasrrat.—South Atlantic States. Gulf States into Sonora. Up the 
Mississippi Valley to Saint Louis. Iowa. Kansas. Nebraska. 
Numerous excellent examples, from the South Atlantic States, of this 
diminutive Rodent, which, with the general appearance of a small house- 
mouse, is instantly distinguished by its generic characters, present very little 
variation either in size, shape, or color. None show the peculiar proportions 
attributed by Audubon and Bachman to their Mus carolinensis. The tail is 
always a little shorter than the trunk. The hind feet range from 0.50 to 0.60 
in length; the ears project beyond the fur, and have a somewhat character- 
istic shape, difficult to describe, represented with indifferent success in Audu- 
bon’s plate above cited. They are rather obovate in shape, and narrow for 
their length; the antitragus is valvular; the interior below is nearly naked 
and flesh-colored; this part is overlaid by the long hairs of the cheeks; the 
rest of the ear is rather coarsely hirsute than closely pilous. ‘The fur is soft 
and silky; above, the color is exactly as in the house-mouse and nearly uniform, 
being merely a little darker along the middle of the back; but all along the 
sides the brown is enlivened with a decided wash of fulvous or pinkish-gray, 
never seen in M. musculus. Generally, this tinge is diffuse, but it sometimes 
forms quite a striking lateral stripe. The tail is distinctly bicolor, but not 
very sharply so. The under parts are whitish, obscured by the plumbeous of 
the roots of the hairs showing through, and generally also noticeably washed 
over with a dilution of the fulvous that tinges the sides. The lips, however, 
are pure white; and the whole oral and mental region, with the upper sur- 
face of the fect, are likewise white. The absolute size, and to some extent 
the range of variation, of this species appear from the table given below. 
