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. 
Hesperomys leucopus Abbott, Cook’s Geol. of N. J., 1868, p. 
758.—Abbott, A Naturalist’s Rambles, 1885, p. 450. 
Peromyscus leucopus Rhoads, Proc. Acad. Nat. Sci. Phila., 
1897, p. 27.—Rhoads, Mam, Pa. and N. J., 1903, p. 80. 
Peromyscus leucopus noveboracensis Rhoads, Mam. Pa. and 
Net) SLOo3.-p Sr. 
Sub-Family MURINE. 
Oxtp Woritp Mick anv Rats. 
Mus musculus Linneus. 
House Mouse. 
PLATES 30 AND 20, Fic. 1. 
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. 
