2 20 NEW GENUS AND SPECIES OF THE SORECIDAN 
in other respects, is to have the ‘ third premolar’ decidedly smaller 
than the ‘ fourth ; ’ while in all the species east of the Rocky 
Mountains (with one possible exception), the same tooth is as large 
as or larger than the other. Of the fact there is no question ; it 
may be observed in an instant, and is unmistakable.” * 
But Bendire’s Shrew, though an inhabitant of the Pacific prov- 
ince, has the third and fourth unicuspids c>f approximately equal 
size, presenting, in this respect, a curiously exceptional condition. 
In the type of Neosorex navigator the ratio of the length of the 
hind foot to the head and body is 36, in the present species it is 26, 
and in Sorex Cooperi 21. In Bendire’s Shrew the proportions of 
the feet differ from those of any known species, agreeing better 
with Neosorex than with any other member of the family. The fore 
feet are large and broad, measuring 1 1 by 4 mm.; the hind feet are 
very long and comparatively slender, measuring 20 by 3.5 mm. 
The fore feet much resemble those of the Blarina brevicauda, but 
the hind feet are both relatively and absolutely much longer. Thus, 
arranging the described American Shrews according to the length 
of the hind foot, Blarina would stand at one end of the series and 
Neosorex at the other, the various species of Sorex coming next 
after Blarina, and the present species next before Neosorex. The 
feet are moderately fimbriate, but not to the extent seen in Nco- 
sorex ; still, the fimbriation is sufficient to indicate a non-fossorial 
habit. 
The tail is almost as long as the head and body. In Neosorex 
it is given as “about equaling or exceeding the head and body.” 
In coloration it differs widely from Neosorex, being unicolor instead 
of bicolor. 
In comparing it with the genus Sorex it is necessary to consider 
only the subgenus Sorex proper, with which it agrees in the pos- 
session of thirty-two teeth. It is found to differ from this subgenus, 
as restricted by Cones, in the following particulars : 
* Bull. U. S. Geol. and Geog. Survey, Vol. Ill, No. 3, 1877, p. 637. 
