MAMMALS-SORICINAE-—SOREX PLATYRHINUS. 
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SOREX PLATYRHINUS. 
Olisorex platyrhinus, Dekay, N. Y. Zool. I, 1842, 22 ; pi. v, f. 1. 
Sorex platyrhynchus, Linsley, Sill. Am. J. Sc. XLIII, 1842, 34G. 
Sorex platyrhinus, Wagner, Suppl. Schreb. Y, 1855, 547. 
Sorex forsteri, Gapper, Zool. Jour. Y, 1830, 201; pi. vii. 
Thompson, Nat. Hist. Vermont, 1842, 26. 
Sp. Ch. —Ears large and conspicuous. Tail scarely longer than the body, and only scantily provided with hair. Upper 
premolars imbricated anteriorly, and decreasing gradually in size. Color above, chestnut or dark brown ; beneath, pale 
cinerous. Length, over two inches. Tail scarcely exceeding 1J inch. 
(No. 1694.)—This very diminutive and slender shrew has an exceedingly attenuated and 
elongated muzzle, which, however, is depressed towards the naked and bilobed tip. Viewed 
from above, there is a slight contraction in the outline of the head, a little anterior to the eye, 
beyond which it swells out again, before tapering to the end. The width of the head is about 
half its length, or a little less. The end of the lower incisor falls about midway between the 
tip of the nose and the eye, which is quite large for a shrew, and distinctly visible without a 
glass. It is situated about halfway between the tip of the nose, and the anterior base of the 
external ear. 
The whiskers are numerous and thickly set; they are black, and the longest reach back nearly 
to the occiput. 
The ears are very large, (for American shrews,) and generally distinctly visible, though 
scarcely projecting beyond the fur. The internal ear is widely open, and the concha is directed 
backwards, as in the genus Mus. The antitragus is very large and semi-circular, and fits closely, 
like a valve, over the meatus, protecting it from the admission of water ; when this is closed, 
however, the rest of the ear is distinctly visible. The concha is semi-circular in shape; its upper 
and lower roots about 0.21 of an inch apart, or the distance from incisors to tip of muzzle ; the 
meatus occupies only the lower third of this distance, and the upper root of the concha does not 
extend beyond the posterior margin of the meatus. There is a vertical partition or flap of skin 
extending across the concavity of the ear corresponding to the helix, which, however, does not 
rise as high as the margin of the concha. The convexity and edge of the ear are rather thickly 
covered with hairs, as also the edges of the antitragus and internal flap ; the remaining portions 
are naked. The greatest distance from the lower root of the concha to its most remote point is 
0.29 of an inch, or about the distance from the root of the concha to the eye. 
The feet are moderately large ; the anterior about as broad as the posterior, and about 0.55 
their length. The fore and hind claws are about equal. The under surfaces of the feet are 
naked, the hinder ones with small tesselated tubercular plates, and the larger tubercles opposite 
the middle of the metatarsus. Besides these, there are four other large tubercles at the bases of 
the first, second, and fifth toes, and between the bases of the third and fourth. 
The hair on the back is about 0.20 of an inch long. The tail is long ; without the hairs, it 
reaches to the meatus, or is about as long as the body ; it is cylindrical, somewhat thickened 
towards the middle, closely annulated, and with hairs springing between the annuli, and 
extending over about three of the latter ; it is terminated by a pencil of long hairs. 
The upper parts are of a rather light chestnut brown, with a hoary aspect, owing to the tips 
being abruptly of this color, but a little lighter penultimately. The under surfaces are grayish 
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