WILD LIFE OF ORCHARD AND FIELD 



Of the Mtiridae we have in the eastern half of 

 the United States the muskrat; the large nest- 

 building wood-rat (Southerly) ; the queer lemming- 

 mouse (S ynaptomys) of the West; the diminutive 

 gray harvest-mouse (Ochetodon) of the prairies 

 and westward; the long-eared red-backed mouse 

 (Evotomys), which is mostly Canadian; and the 

 two genera Microtus and Peromyscus, whose rep- 

 resentatives are our most common field-mice. 



The genus Microtus includes a great tribe of 

 voles scattered over most parts of the world, of 

 which no less than seventy different species and 

 varieties are recognized in North America alone by 

 the latest monographer ; which simply shows how 

 numerous and widespread they are and how each lo- 

 cality impresses the voles that dwell there with some 

 more or less noticeable peculiarity of color or pro- 

 portion of parts. Thus the voles that dwell on 

 Gull Island, at the entrance to Long Island Sound, 

 and those on little Muskeget Island, near Nantucket, 

 are each given specific names to mark the differ- 

 ences that their isolated life has brought about 

 in the course of time. With these fine distinctions 

 the reader need not disturb his mind, but content 

 himself with remembering that in the East all the 

 voles, or meadow-mice, are more or less varieties of 



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