1 8 EVERMANN AND CLARK 



13. Peromyscus maniculatus bairdi (Hoy & Kennicott). 



Michigan White-footed Mouse. 



This species is not as abundant as the Common White-footed 

 Mouse. It does not appear to venture into woodlands or swamps, 

 but seems to prefer dry, open situations such as the edges of fields 

 and grassy pastures. Its general distribution is more northern 

 than that of its near relative, P. leucopus noveboracensis. It is 

 very abundant in the sand dunes that border Lake Michigan. 

 At Maxinkuckee it is probably not uncommon, though we have 

 seen only 3 examples. One was found dead on the railroad track 

 November 3, 1904. Another captured at the gravel pit October 

 29, 1906, gave the following measurements: Length 118 mm.; 

 tail 48; hind foot 9; ear 10; girth 55. A third example was captured 

 November 3, 1906, in a cornfield east of the lake. 



The young of this mouse differ from the adult in being drab in 

 color instead of yellowish-brown. On one occasion when trapping 

 these mice for specimens it was observed that they were quite 

 seriously infested by fleas. The examples thus afflicted could 

 usually be recognized at once by their having the hair gnawed or 

 scratched out from about the root of the tail. 



This mouse can be distinguished from its more common relative 

 (the Common White-footed Mouse) by its smaller size, smaller 

 ears and feet, and shorter tail, the tail being more thickly hairy and 

 more sharply bicolor. The adult is yellowish-brown, with a sooty 

 dorsal band; belly white; feet not quite white; tail bicolor. Length 

 4j inches, tail ij inches. 



14. Microtus pennsylvanicus (Ord). 

 Field Mouse; Meadow Mouse; Vole. 



The Meadow Mouse is abundant in all suitable situations about 

 the lake. The extensive areas of semi-marshy grassy land supply 

 an ideal habitat for this noxious but interesting little animal. Wher- 

 ever there are meadows or marsh ground covered with grasses 

 there these mice will be found, their labyrinthine runways forming 

 an intricate network under the dead grass where their nests are 

 numerous and usually quite conspicuous. These runways are very 



