162 Order RODENTIA 



are white. The tail is bicolored, dark on the upper part, whit- 

 ish on the under part. In the immature mouse, the upper parts 

 are a dull brown or gray, the under parts white. 



Length measurements: head and body 3-4 inches (78-100 

 mm.) ; tail 23/^-3^8 inches (60-85 mm.) ; over-all 5;^-7i4 

 inches (138-185 mm.) ; hind foot M~% inch (18-22 mm.) ; ear 

 from notch Y^-^ inch (15-19 mm.). 



The skull is 24.5-28.0 mm. (about 1-1 i/s inches) long; the 

 width across the z3'gomatic arches just behind the infraorbital 

 plate is more than 12 mm. Part of the skull is shown in fig. 

 74//. Dental formula: I 1/1, C 0/0, Pm 0/0, M 3/3. 



The white-footed mouse closely resembles the deer mouse 

 and the cotton mouse. 



Life History. — The white-footed mouse lives in forests, fig. 

 1, brushlands, river bottoms, forest edges, and even in brushy 

 areas extending out into prairies. Probably 3 to 12 mice, some- 

 times even more, per acre occur in these habitats. A white- 

 footed mouse may be found under a log, within a stump, in a 

 once-abandoned bird's nest, or in a shallow burrow. It may make 

 its nest in, on, or above the ground. If a home in a burrow 

 proves too damp, the white-footed mouse may move into a de- 

 caying log or into a tree stump. In the fall, it may move to an 

 unused bird's nest, such as that of the goldfinch, after working 

 diligently a few nights to build a dome over it and arrange a 

 soft lining. It may nest in a woodpecker hole or a bird box near 

 timber; it rarely enters inhabited buildings. 



Breeding may take place in all except the very coldest months 

 of the year, but the majority of young are produced in spring, 

 early summer, and fall. The white-footed mouse is probably as 

 prolific as the deer mouse. A mature female gives birth yearly 

 to at least four litters, with four or five young in each litter. 

 The young are hairless and blind at birth. They grow rapidly 

 and become independent of family ties probably when they are 

 scarcely more than a month old. 



The white-footed mouse is nearly omnivorous. It normally 

 feeds on seeds of wild herbaceous plants, nuts, buds, fruits, and 

 insects; if given an opportunity it eats grains and pantry items. 



Signs. — Tracks and droppings of the white-footed mouse 

 resemble those of the deer mouse, fig. 31, but they are slightly 

 larger. The home of the white-footed mouse is described above 

 under life history. 



