212 Field Museum of Natural History — Zoology, Vol. XL 



'Area of intergradallon 



Map illustrating approximate distribution of Red-backed Mice or Red-backed Voles (Evolomys) 

 in eastern United States. 



Evotomys gapperi (Vigors). Type locality — Vicinity of Lake Simcoe, Ontario. 

 Description as previously given. 



Evotomys g. loringi Bailey. (Proc. Biol. Soc. Wash., XI, 1897, p. 125.) Type 

 locality — Portland, Traill County, North Dakota. Smaller and somewhat 

 brighter colored than gapperi and with smaller skull. 



Evotomys g. ochraceus Miller. (Proc. Bost. Soc. Nat. Hist., XXVI, 1894, p. 193.) 

 Type locality — Mt. Washington, Coos Co., New Hampshire. Larger and 

 darker than gapperi. 



Evotomys g. rhoadsi vStone. (Amer. Nat., XXVII, 1893, p. 55.) Type locality — 

 May's Landing, Atlantic Co., New Jersey. About the size of gapperi, but darker 

 and with shorter tail. 



Evotomys proteus Bailey. (Proc. Biol. Soc. Wash., XI, 1897, p. 137.) Type 

 locality — Hamilton Inlet, Labrador. Largest of our northeastern forms. 



Evotomys carolinensis Merriam. (Amer. Jour. Sci., 3rd ser., XXXVI, 1888, p. 460.) 

 Type locality — -Roan Mountain, Mitchell Co., North Carolina (altitude 6,000 

 ft.). Dorsal stripe dark chestnut and not sharply defined, shading into color 

 of sides. 



