KEY TO LAND MAMMALS OF NORTHEASTERN NORTH AMERICA IO3, 

 SPECIES OP MICROTtJS 



Fur dense and mole-like ; claws on front feet long- 

 est (subgenus P i t y m y s ) M.pinetorum, p. 103 



Fur not dense and mole-like; claws on hind feet 

 longest (subgenus Microtus) 

 Face or muzzle distinctly yellowish 



Total length about 180 (6f ) ; muzzle 



patches pale M. terr aeno vae, p. 104 



Total length about 165 (6J) ; muzzle 



patches dark M. chrotorrhinus, p. 104 



Face or muzzle not distinctly yellowish 



Total length often over 200 (8); color 



very pale M.breweri, p. 105^ 



Total length seldom if ever reaching ' 



200 (8>; color dark 



Teeth weak ; front teeth protruding 

 forward ; the row of cheek teeth 



less than i basal length of skull.. . M. enixus, p. 105 



Teeth strong; front teeth not pro- 

 truding forward ; the row of cheek 

 teeth more thau J basal length of 

 skull 



Skull not very broad (the com- 

 mon field mouse of the eastern 



United States) M. pennsyl van icus, p. 105 



Skull very broad (confined to 

 Great Gull island o6f the east- 

 ern end of Long Island, New 

 York) M. nesophilus, p. 107 



Microtus pinetorum (Le Conte) Piiie mouse 

 Fur dense velvety and mole-like, eyes and ears very small, claws on front feet 

 longest; color of adults dull reddish brown ; young slaty. (pinet6rum; Lat., 

 of the pines) 



The pine mouse inhabits dry sandy soil (usually in thickets and open 

 woods) in the austral zones and lower part of the transition zone of the 

 United States from the Atlantic coast west to Missouri and Indian terri- 

 tory. It is divisible into four or more subspecies, one of which occurs 

 within our limits. 



Microtus pinetorum scalopsoides (Audubon & Bachman) 

 Northern pine mouse 



1841 Ar V i c 1 a scalopsoides Audubon & Bachman, Proc.acad. nat. sei. 



Philadelphia. Oct. 1841. 1:97. (Long Island, New York) 

 1896 Microtus pinetorum scalopsoides Batchelder, Proc. Boston 



soc. nat. hist. Oct. 1896. 27:187. 

 1900 Microtus pinetorum scalopsoides Bailey North American fauna » 



6 June 1900. no. 17, p. 64. 

 Adults reddish brown, lighter than in the southeastern pine mouse ( M. pine- 

 torum pinetorum) of the lower austral zoue. Total length, 125 (5) ; tail 

 vertebrae, 22 (^) ; hind foot, 16 (|). (scalops6ides; Gk., mole-like) 



