420 FIELD MUSEUM OF NATURAL HISTORY ZOOLOGY, VOL. XL 



Map illustrating approximate distribution of the Shrews belonging to the genus Microsorex in 

 eastern United States and Canada. 



Microsorex hoyi (BAIRD). Type locality Racine, Wisconsin. Description as 

 previously given. 



Microsorex alnorum (PREBLE). (N. Amer. Fauna, No. 22, 1902, p. 72.) Type 

 locality Robinson Portage, Keewatin, Canada. Grayer than hoyi above, 

 without brownish on under parts; feet larger and also cranial differences; ap- 

 proaches very closely Microsorex eximius (Osgood). 



Microsorex winnemana PREBLE. (Proc. Biol. Soc. Wash., XXIII, 1910, p. 101.) 

 Type locality Fairfax County (bank of Potomac River near Stubblefield 

 Falls), Virginia. "Similar to Microsorex hoyi, but considerably smaller; brain- 

 case proportionally higher and more rounded" (Preble). Total length of 

 type about 3.1 in. (78 mm.); tail vertebrae, about 1.2 in. (30 mm.). 



Genus NEOSOREX Baird. 



Neosorex Baird, Mammals N. Amer., 1857, p. n. Type Neosorex 

 navigator Baird. 



Fourth upper incisor well developed; no second- 

 ary cusps on inner side of canines or incisors ; brain- 

 Hind foot of Neosorex case broad; feet with fringe of bristly hairs. 



palustris. 



Dental formula: I. 



2-2 



C. 



o-o 



, Pm. 



I-I 



3-3 



