224 
NEW GENUS AND SPECIES OF THE SORECID.E. 
of the malar process of the maxillary bone to the glenoid fossa. 
The anteorbital foramen is. very large. The rostrum is strongly 
compressed in front of the molariform teeth, its sides rising almost 
vertically to form the lateral walls of the anterior portion of the 
nasal chamber. The width opposite the third unicuspid is 2.20 
mm., while the distance across the molars is 6 mm. — or 2.72 times 
greater. The pterygoid hamuli are slender styliform processes 
extending almost directly backward. 
The mandible presents no marked peculiarities. The horizontal 
ramus is stout and slightly convex. The coronoids are large and 
high, diverge outward, and incline a little forward. The styliform 
angular processes are relatively short for a Shrew ; they are 
parallel, and are directed backward, and slightly downward. 
Nothing whatever is known of the habits of Bendire’s Shrew. 
Its structure, however, leads to the belief that it is not amphibious 
like Neosore. r, nor an inhabitant of dry uplands, like the various 
species of Sore: r proper, but that it is a marsh species, dwelling in 
wet meadows, and occasionally taking the water either in the pur- 
suit of its prey or as a means of escape from its enemies. 
In view of its isolated position, speculations concerning its 
genetic affinities are perhaps unwarrantable ; still, a somewhat 
critical study of its peculiarities shows that, whatever its past 
history, it cannot be regarded as intermediate between Sorex and 
Neosorex. Neither can it have been derived from Neosorex. 
H ence the logical inference is that Atophyrax , in common with 
Neosorex , was early differentiated from a group of thirty-two- 
toothed Shrews of which the genus Sorex contains the nearest 
living allies. Having abandoned a fossorial for, in the one case 
a natatory, in the other a paludal habit, Neosorex and Atoph- 
yrax doubtless began to diverge in the same direction, their dis- 
tinctive features having been developed and intensified as their pe- 
culiarities of habit became fixed — each retaining in different de- 
grees of modification certain characteristics of the original stock. 
For the very accurate drawings accompanying this paper I am 
indebted to the kindness of Mr. Ernest E. T. Seton, who executed 
them, under my supervision, from the alcoholic specimen. 
