ATDPIIVRAX BEXDIRII. 221 



a. The inner lobe of the upper front incisor is small. 



b. The fifth unicuspid is nearly half as lari^e 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 Microsorcx). 



d. The depth of the rostrum (including^ the closed jaw) is equal 

 to that of the cerebral portion of the cranium. 



c. The coronoid process of the mandible is large and divcrocnt 

 (as in Ncosorcx, and somewhat as in Notiosovcx). 



f. The insertion of the lower incisor is anterior to the middle of 

 the second unicuspid. 



o\ The lower incisor has but two denticulations. 



To recapitulate : Bendire's Shrew differs from all existing fen- 

 era in external, cranial, and dental characters. It has affinities 

 with both Sorcx 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-thrrds 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 Sorccidce. Vault of cranium hicrher, 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, meetino- the 

 parietals at a more abrupt angle than in Sorex, instead of rounding 

 up into the vault of the cranium as in Neosorex. Rostrum strongly 



* Atoph'-yrax : aroitoi, anomalous; v/3a$=sorex. 



