258 ECONOMIC MAMMALOGY 



venter) : "food consists mainly of nuts and acorns, but fruits, berries 

 and lichens also are eaten. When feeding on nuts their flesh has a 

 delicious nutty flavor." Texas fox squirrels (S. n. limitis) : "pecan, 

 hickory, oak and walnut trees furnish their food," but they take also 

 cypress cones and other food. 



The same author has discussed also the squirrels of North Dakota, 9 

 his report furnishing the following items: Pale flying squirrel (Glau- 

 comys sabrinus canescens) : rarely abundant enough to be of economic 

 importance, but, so far as known, harmless. Seldom disturbs culti- 

 vated crops. Eats tree seeds, but pays for them by scattering those not 

 eaten and thus seeding the forest floor. Minnesota gray squirrel (Sciu- 

 nts carolinensis hypophaeus) : in native habitat its food is largely 

 acorns, but includes many other nuts and seeds and grain. Northern 

 red squirrel (S. hudsonicus) : "food consists of acorns, nuts, seeds, 

 mushrooms and occasionally birds' eggs" ; injurious when it gets into 

 corn cribs and grain bins. Northern chipmunk (Eutamias minimus 

 borealis) : "found feeding extensively on chokecherries" ; also takes 

 acorns and seeds and berries of various plants. Does some damage 

 to gardens and edges of grain fields, but not a serious pest. Pale chip- 

 munk (E. m. pallidus) : eats a great variety of nuts, seeds, berries and 

 some vegetation, does some damage to crops, but is easily controlled 

 by traps and poisons. Gray eastern chipmunk (Tamias striatus gri- 

 seus) : eats a great variety of nuts, seeds, grains, berries and some 

 green vegetation, occasionally insects, frogs and lizards. Does some 

 damage, but easily trapped and poisoned. Thirteen-striped ground 

 squirrel (Citellus tridecemlineatus) : food largely seeds, grains and 

 nuts, but takes also berries, green vegetation, "numerous insects," mice, 

 birds, etc. Stomachs examined contained a "considerable portion of 

 grasshoppers, crickets, caterpillars, beetles, ants, cocoons, insect eggs, 

 and even traces of flesh, hair of small mammals, and feathers of birds." 

 Does some damage, but easily controlled. "But for their natural ene- 

 mies, which are legion, it would be impossible to raise crops within 

 their territory. They are constantly preyed upon by many species of 

 hawks and some owls, and by foxes, weasels, skunks and badgers, so 

 that in spite of their rapid increase their numbers are usually kept 

 somewhat within bounds. However it is necessary over much of their 

 range to supplement the work of their natural enemies by the sys- 

 tematic use of poison." Its pale relative (C. t. pallidus} has about the 



9 Bailey, A biological survey of North Dakota, N. Amer. Fauna, No. 49, 1926. 



