ATOPHYRAX BENDIRII. 
22 1 
a. The inner lobe of the upper front incisor is small. 
b. The fifth unicuspid is nearly half as large as the fourth, and is 
not at all crowded. 
c. The distance across the molars (outside to outside) is greater 
than half the width of the cranium (as in Microsore: x). 
d. The depth of the rostrum (including the closed jaw) is equal 
to that of the cerebral portion of the cranium. 
e. The coronoid process of the mandible is large and divergent 
(as in Neosore: v, and somewhat as in Notiosorex). 
f. The insertion of the lower incisor is anterior to the middle of 
the second unicuspid. 
g. The lower incisor has but two denticulations. 
To recapitulate : Bendire’s Shrew differs from all existing gen- 
era in external, cranial, and dental characters. It has affinities 
with both Sorex and Neosorex and is in some respects intermediate 
between them, though in other respects it passes Neosorex in the 
direction away from Sorex.' It also possesses characters of its own 
not found in either of these genera. I propose for its reception 
the genus 
ATOPHYRAX. * 
Generic characters. — Teeth thirty-two, not crowded. Upper 
front incisor with basal hook about two-thirds as large as next suc- 
ceeding tooth ; subterminal notched lobe small, connivent with its 
fellow. Unicuspids five, imbricating, not crowded; fifth nearly 
half as large as fourth, with a well-developed conical cusp. Upper 
molariform teeth constituting just half the length of the entire 
series. Lower premolar markedly bicuspidate. 
Rostrum much produced, occupying a little more than five-ninths 
of the entire length of skull. Greatest breadth of skull considera- 
bly less than half its length, and equal to the distance from front 
incisor to hinder margin of palate. Posterior margin of palate 
situate far behind a point midway between the front incisor and 
foramen magnum. Base of cranium shorter than in any other 
American group of Sorecidce. Vault of cranium higher, more 
arched laterally, and narrower than in Neosorex (somewhat as in 
Sorex), the cerebral portion rising considerably out of line with the 
rostrum. Sagittal, lambdoidal, squamous, and zygomatic crests 
well-marked. The occipital plane slopes forward, meeting the 
parietals at a more abrupt angle than in Sorex, instead of roundino- 
up into the vault of the cranium as in Neosorex. Rostrum strongly 
* Atoph'-yrax : aroitoi, anomalous; vpaB,= sorex. 
