8o MAMMALS OF PENNSYLVANIA AND NEW JERSEY. 



mouse {P. gossypinus) , similar in appearance to Rafinesque's mouse but quite 

 distinct in other characters, being larger. The latter does not come nearer 

 our limits than eastern Virginia (possibly southeastern Maryland and south- 

 ern Delaware), but the former has been taken in Maryland and may occasion- 

 ally straggle along the eastern foothills of the Alleghany Mts. across the Pa. 

 border. 



Distribution in Pa. and N.J. — Upper austral regions of both states in uni- 

 versal abundance, except in southern N. J., in the pine barren and coast 

 region, where it may be said to be rare but not absent from any place con- 

 tiguous to woods or thickets. Found in its most typical form in southern 

 N. J. merging into subspecies noveboracensis at elevations of about looo to 

 1500 ft. 



Habits, etc. — Essentially the same as those above given for Miller's Deer 

 Mouse. Often nesting in deserted birds' nests among thickets and briars in- 

 stead of in hollow trees and logs as do the more northern forms. This 

 animal does some damage to grain crops near woodland, carrying away and 

 storing large quantities for so small an animal in a short time. As this is 

 done chiefly in winter where crops have been neglected or unhoused, the fault 

 lies less with them than with the farmer. Their chief diet is nuts, buds, bark, 

 seeds and tuberous roots of woodland growth so that they are not to be ac- 

 counted among "noxious" animals. Although so abundant they seem to 

 rarely fall a prey to hawks and owls as compared with the meadow mice or 

 even the shrews. This may be determined by the ratio of their skulls in the 

 pellets regurgitated by rapacious birds. Owing to their exquisite perception 

 of danger in all its forms and their great agility in leaping and cHmbing, it is 

 probable that they likewise escape being made a very large part of the diet 

 of weasels, foxes, skunks, etc., as compared with the more subterranean mice 

 and shrews. 



Description of species. — P. leucopus and its northern ally P. I. noveboracensis 

 may be distinguished from the P. canadensis group by the relative shortness 

 of their tails, that member being considerably less than half the entire length 

 of the animal. In canadensis the tail is longer than the head and body and 

 the prevailing color is a dull or light brownish gray, in fact very little real 

 color about it, but in the leucopus group the bright and dark russet or fawn 

 shades are a striking feature, so resembling those of a deer as to suggest the 

 name, deer mouse. A comparison of deer mice from the lower Delaware 

 valley with those found in the upper transition areas of Pennsylvania shows 

 that noveboracensis is of a duller grayish russet on the back and sides, the 

 richness of color observable in leucopus being dimmed by the greater amount 

 of gray and black-tipped hairs. The darkly contrasting median dorsal area 

 of blackish is more defined in leucopus, and the fur of under parts is purer 

 white, showing less the plumbeous bases of hairs. The difference in size is 



