new Species of Water-Shrew. 373 
collection of specimens representing the family Soricide in 
the Zoological Museum of the Imperial Academy of Sciences 
at St. Petersburg, which, owing to the kindness of Dr. Strauch, 
I have been enabled to examine. 
Sorex hydrodromus. 
Scareely larger than S. mznutus, and therefore much smaller 
than S. palustris, which it also differs from in dentition, but 
resembles in the fringed condition of the digits of the manus 
and pes. The tail is nearly as long as the head and body and 
is clothed rather thinly with moderately long hairs, which do 
not form a fringe ; in the form of the muzzle and ears there 
is nothing peculiar or different from that of S. ménutus; the 
feet, however, differ remarkably in the possession of fringes to 
the digits both of the manus and pes, as well as or even better 
developed than in Crossopus fodiens ; a thick comb-like fringe 
of stiff hairs also extends along the outer and inner margins 
of both manus and pes, being especially dense and well deve- 
loped along the outer margins. 
Fur reddish brown above, yellowish brown beneath; chin, 
throat, and chest with greyish-tipped hairs; the base of the 
hairs both above and beneath dark bluish grey. 
The teeth closely resemble those of S. vu/garis; as in that 
species the third incisor is the largest and longest of the uni- 
cuspidate teeth ; the first max- 
illary tooth is very nearly 
equal to the second incisor and 
quite intermediate in size be- 
tween the third incisor and the 
second maxillary tooth; the 
third maxillary tooth is even 
more internal than in S, vul- 
garis, in this respect resem- 
bling the American represen- 
tatives of that species, and its long axis is at right angles to 
the direction of the jaw, its inner and posterior convex margin 
fitting into the concavity on the inner and anterior side of the 
fourth maxillary tooth. The mandibular teeth closely re- 
semble those of S. vulgaris. 
Length: head and body 53 millim. ; tail 45; eye from end 
of muzzle 93; ear, length 6}; elbow to end of middle digit, 
without claw, 13, manus 6, pes 13 ; distance between tips of 
first upper incisor and last premolar 34. 
Hab, Unalaska Island, Aleutian Islands. 
