RODENTIA 277 



was found that in addition to taking insects, the "stomachs of all speci- 

 mens procured contained scorpions, and many were distended with 

 them to the exclusion of other food. One contained the hair and flesh 

 of a mouse." 7 The stomach of one eastern desert grasshopper mouse 

 (O. /. melanophrys) was found "packed full of scorpions." 8 



The food of harvest mice (Reithrodontomys) consists chiefly of 

 seeds (mostly of grasses), with some grain and a little green vege- 

 tation. They are usually not abundant enough to do much damage, but 

 when numerous they may be quite injurious. 9 



The white-footed mice, or deer mice, genus Peromyscus, with many 

 species and subspecies, are the most generally distributed and abundant 

 North American mammals, rivalled in this respect only by the meadow 

 or field mice, of the genus Microtus. They are very prolific breeders, 

 having a number of litters per annum, of five or six young each, 10 

 hence are a potential menace to crops. Plagues of white-footed mice 

 have occurred, similar to those of lemmings and voles, such as the one 

 of 1872-1873 in South America. 11 The food habits of the various 

 species are very similar, though not exactly the same, and of course 

 depend to some extent upon the food available. They are rather om- 

 nivorous. "Very few feed extensively upon green and succulent food 

 such as is taken by the meadow mice, but nearly all prefer dry-land 

 food, especially seeds and small nuts" ; mostly seeds of native shrubs, 

 weeds and grasses, but they take grain when they live about the edges 

 of fields, taking also meat, and sometimes gnawing the bark of young 

 fruit trees and nursery stock. 12 "So small, so numerous, and so widely 

 distributed are they that they are not easily controlled, except by their 

 natural enemies, which are numerous. They are favorite prey of all 

 small owls and even of many of the larger owls, and form an im- 

 portant article of diet for weasels, skunks, badgers, foxes and such of 

 the other small predatory species as occur within their range. Reason- 

 able protection of the species that prey upon them, especially the owls, 



T Merriam, N. Amer. Fauna, No. 3, pp. 59, 61, 1890. 



8 Mearns, U. S. Natl. Museum Bull. No. 56, p. 371, 1907. 



"Bailey, Farmers' Bull., No. 335, 1908; N. Amer. Fauna, No. 49, p. 80, 1926. 

 Burnett, Office Colorado State Entom. Circular No. 25, p. 8, 1918; says food like 

 that of grasshopper mice, but perhaps destroys more grain. 



10 Burnett, Office Colorado State Entom. Circular No. 25, 1918. Bailey, N. Amer. 

 Fauna, No. 49, p. 78, 1926. 



11 Hudson, Naturalist in La Plata, pp. 64-65, 1892. Lantz, U. S. Biol. Surv., Bull. 

 No. 31, pp. 52-53, 1907. 



12 Osgood, Revision of the mice of the American genus Peromyscus, N. Amer. 

 Fauna, No. 28, pp. 27-28, 1909. 



