THE MAMMALS OF NEW JERSEY. 75 



mice frequently take up their abode and make free with what- 

 ever nest materials they may find. Sometimes, too, they are 

 caught in the farm house in winter. 



The white-footed mouse is the most frequent species caught 

 in the mammalogist's traps and sO' abundant are they in some 

 places that it seems as if they have to be exterminated before 

 any other species has an opportunity to test the qualities of the 

 trap. They prove a nuisance also- in chewing the eyes, ears and 

 other parts of specimens caughts in traps before they can be 

 gathered up. Even individuals of their own species are de- 

 voured by these canabalistic little animals, not only dead ones 

 in a trap but. captive live ones that have been killed in conflict 

 with their fellow prisoners. 



The attempt has been made tO' divide this species into a north- 

 ern and southern race, but the distinctions of color upon which 

 the difference rests are sO' fine that they defy my powers of 

 observation at least so far as New Jersey specimens are con- 

 cerned. Those who care to call the animal of the northern coun- 

 ties P. leucopus noveboracensis (Fischer), however, are free to 

 do so, and should find it duller above and tinged with gray be- 

 neath. 



Hcsperomys leucopus Abbott, Cook's Geol. of N. J., 1868, p. 

 758. — Abbott, A Naturalist's Rambles, 1885, p. 450. 



Pcromyscus leucopus Rhoads, Proc. Acad. Nat. Sci. Phila., 

 1897, p. 27. — Rhoads, Mam. Pa. and N. J., 1903, p. 80. 



Pcromyscus leucopus noveboracensis Rhoads, Mam. Pa. and 

 N. J., 1903, p. 81. 



Sub=FamiIy MURIN/G. 



Old World Mice and Rats. 



Mus musculus Linnaeus. 

 House Mouse. 



Plates 30 and 29, Fig. i. 



Length 6.70 inches. General color gray slightly tinted with 

 yellowish brown, especially on the face and shoulders, dusky on 

 the back, below paler gray sometimes buffy. 



