This animal agrees with the S. constrictus in having two lateral incisors more
in the upper jaw than some other species of the genus, but the Sorex brevicaudus
of Say is described by Dr. Harlan as having five lateral incisors (“ minute false
molars ”) on each side, and the same thing occurs in the following species.
When compared with a specimen of the water-shrew in the British Museum, the
colour of its fur appeared different, the points of the teeth darker, the ears smaller,
and the tail longer than in the water-shrew. Several specimens of this animal
were obtained, but the descriptions were drawn up from the prepared skins, and
some uncertainty consequently exists as to the true shape of the tail. The
S. palustris most probably lives in the summer on similar food with the water-
shrew ; but I am at a loss to imagine how it procures a subsistence during the
six months of the year in which the countries it inhabits are covered with snow.
It frequents borders of lakes, and Hearne tells us that it often takes up its abode
in beaver houses.
[4.] 2. S o r e x F o r s t e r i . (Richardson.) Forster’s Shrew-Mouse.
Shrew, No. 20. F orster. Phil. Trans, vol. Ixii, p. 381.
Sorex Forsteri. Richardson. Zool. Joitm. No. 12, April, 1828.
Sorex ( Forsteri) cauda tetragonSt longitudine corporis, auriculis brevibus vestitis, dor so xerampelino, ventre murino.
Forster’s Shrew-mouse, with a square tail as long as the body, short furry ears, back of a clove-brown colour,
belly pale yellowish-brown.
This little animal is common throughout the whole of the fur countries to the
67th degree of latitude, and its minute foot-prints are seen every where in the
winter, when the snow is sufficiently fine ,to retain the impression. I have often
traced its pathway to a stalk of grass, by which it appears to descend from the
surface of the snow, but a search for its habitation by removing the snow was
invariably fruitless. I was unable to procure a recent specimen, and the following
description is drawn up from one prepared by Mr. Drummond. It is the
smallest quadruped the Indians are acquainted with, and they preserve skins
of it in their conjuring bags. The power of generating" heat must be very great
in this diminutive creature to preserve its slender limbs from freezing when
MAMMALIA. 7
the temperature sinks 40 or SO degrees below zero. The Sorex Forsteri approaches
the iS. tetragonurus of Desmarest in dimensions, and agrees with it in
some other points.
DESCRIPTION.
Dental formula, interm, incisors £, lateral incisors grinders M 32.
The teeth are white, brightly tinged with chestnut brown on the points. The upper
intermediary incisors have each a posterior obtuse lobe. The lateral incisors of the upper
jaw are crowded and somewhat tiled ; 'the four anterior ones of a side are broad and obtusely
conical, the fifth is flatfish on the crown. The first grinder is smaller than either of the two
which .succeed i t ; and the fourth is the smallest of all. In • the lower jaw the intermediary
incisors have two distinct obtuse posterior lobes, and a slight undulation producing the rudiment
of a lobe towards their points :. the. lateral incisors have a central mammillary point;
and the anterior grinder is a little larger than the other two, , The muzzle is very slender,
and has a naked and a deeply lobed tip. The whiskers reach to the occiput, and are
composed of a few white hairs, intermixed with many black ones. The ear is as long
as the fur of the head, and is clothed within and without, but particularly on its
margins, and folds,'with hairs of the same colour arid length of those on the crown of
the head. It is rounded, but from a small fold of its upper margin appears pointed. Its
circumference is ample for the size of the animal. There is a semicircular lobe projecting
from the inferior margin of the ear, and covering the auditory opening, and above it there is a
transverse fold. The ear is not perceptible until the fur is blown aside. The fu r forms a
fine, short, close coat, which on the dorsal aspect of the animal has a grayish-brown or clove-
brown colo.ur, and on the ventral, aspect a dull yellowish-brown. The tail is four-sided
and tapers gradually from the root to its extremity, which is terminated by a pencil of
hairs. It is covered with dark-brown hair above, and pale, yellowish-brown hair beneath.
The feet are five-toed, and are clothed with short, adpressed, pale yellowish-brown hairs.
The nails are slender and white.-
• ’Dimensions.
Length of head and body
Inches. Lines.
» . 2 3 Length from upper incisors to nostrils
Inches. Lines,
. 0 2
„ of tail .. . . . 1 3 Height of the ear . 0 2
„ of head . . 0 9 |