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ECONOMIC ZOOLOGY 



so-called field or short-tailed mice, or voles, of which there are over 

 fifty kinds known in the United States. For convenience they may be 

 considered in two groups, the "meadow mice," genus Microtus, and the 

 "pine mice," genus Pitymys, Fig. 156. The latter may be distinguished 



P 



FIG. 156. Upper figure, meadow mouse, Microtus pennsylvanicus. X%. 

 Lower figure, pine mouse, Microtus (Pitymys) pinetorum. X%. (From Lantz, 

 Meadow Mice in Relation to Agriculture.) 



from the former by its closer, smoother fur, its reddish-brown color and 

 its subterranean habits. 



The meadow mice make smooth, branching runs on the surface of 

 the ground, beneath the grass and leaves; the winter nest is under 

 ground, the summer nest is a large ball of dried grass on the surface 

 of the ground. These mice are found, especially in open fields, in 



