Descriptions of East Asiatic Mammals 57 
tail 214 inches, hind foot % inch; of brachyotis, head and body 
2% to 2% inches, tail 2y 2 to 2% inches, hind foot % inch. 
It is possible to distinguish between these two Siberian forms of 
Water Shrews by the fact that brachyotis is blackish with whit- 
ish underparts, and argenteus brown with underparts dull white. 
The Old World Water Shrews are good swimmers. They 
feed upon a variety of insects and upon shrimp-like animals that 
live in the water. They have been known to take very small 
fish and to cause damage in fish hatcheries. In captivity they 
will kill and eat frogs. From 4 to 8 naked young are born. The 
nest cavity is proportionately larger than that of Sorex araneus. 
the white-toothed shrews 
(subfamily crocidurin^e) 
The White-toothed Shrews are confined to the Old World. 
They are found chiefly in the warmer parts but may also 
ascend mountains in the tropical zones to high altitudes. Like 
the Soricinse, they have given rise to water-dwelling genera 
such as Chimarrogale and Nectogale, which have adaptations 
for swimming. The terrestrial Crocidurinae are distinguished 
from the True Shrews not only by their unpigmented teeth but 
by the sprinkling of long hairs on the tails in some genera and 
the presence of four instead of five cusps on the last lower 
molar. 
The non-burrowing terrestrial White-toothed Shrews include 
two genera, Suncus and Crocidura, both of which groups have 
the tail thinly clad with scattered long hairs. For convenience 
they will be treated as full genera ; but they can be regarded as 
subgenera, since they differ only by the presence or absence of 
the front one of the two upper premolars (the last unicuspid). 
This tooth is never very large and in some species is exceedingly 
tiny. To make an important distinction between its absence or 
presence seems arbitrary, if one considers that occasional ani- 
