FAMILY MIJRIDAK 



To this family belon<^' such well known rodents as liouse-iuice, 

 house-rats, field- arid meadow-mice, muskrats, etc. 



The rodents of this family vary considerably in size, the harv- 

 est mouse ( ReithrodontomyH) measuring about 51^ inches \n length, 

 while the muskrat (Ondatra) measures about 22 inches. 



Members of this family are found in all parts of the world, 

 and on account of their wide distribution and large numbers, some 

 of the species are the most destructive of all the rodent family. 

 They destroy hay and grain in the fields, vegetables in the garden, 

 trees in the orchard, merchandise of different kinds, cotton, silk, 

 and wool fabrics, etc. They also transmit disease from place to 

 place fatal to man. 



Fig. 2. Grasshopper Mouse (Onycho)iii/s leucogaster arcticeps) . From 

 a specimen taken at Little Medicine, Wyoming, October 15th. Original. M. A. 

 Palmer, Delineator. 



SUBFAMILY CRICETINAE 

 Genus Onijchomys 

 Body stout, pelage, bicolored, upper sides, head and back 

 tawny or grayish, underparts white, with separating line sharply 

 drawn. Immatured pelage of young blue, similar to young Pero- 

 myscus. Tail short and tapering, bicolored. 

 Colorado Species of Grasshopper-Mice. 



Long-nosed Grasshopper-Mouse, Onychomys lencog-ister arcti- 

 ceps. 



Pale Grasshopper-Mouse, Onychomys leucogaster melanophrys. 



The distribution of these two species show^s that they are found 

 over most of the State. The food of grasshopper-mice consists of 

 seeds of various kinds, grain, insects such as beetles, grasshoppers, 

 crickets, flesh of other mice, etc. From our observations, the grain 

 eaten is waste grain left on the ground or in shocks in the fields. 

 It is hardly possible that growing grain is eaten to any great ex- 

 tent. From their habit of feeding on weed seeds and injurious in- 

 sects, they may be classed, for the present, as beneficial. 



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