1250 THE RODENTS 



as chipmunks, constitute a group serving to connect the two squirrels with the sus- 

 liks. Having molar teeth of the same type, the chipmunks are indeed so closely 

 allied to the true squirrels that Dr. Forsyth-Major proposes to include them in the 

 same genus. They differ, however, from both the spiny squirrels and the true 

 squirrels in the possession of pouches inside the cheeks; on which account they 

 may, for the present at least, be allowed to stand under the generic title by which 

 they are commonly known. They are further characterized by the sides, or the 

 back and sides together, being marked by longitudinal white or grayish- white stripes 

 bordered by black bands. The ears are of medium size or small, and are never 

 tufted with long hair; while the tail is shorter than the head and body, flattened, 

 and rather wide. The skull is generally like that of the true squirrels, but rather 

 narrower and more slender, and the first premolar tooth in the upper jaw is either 

 absent or very minute. 



The common American chipmunk (Tamias striatus^, together with its numer- 

 ous varieties, is distinguished by having two white strips, each bordered with black, 

 and a simple black stripe running down the middle of the back; and has also two 

 white stripes, separated by a black one, above and below the eye. It is about the 

 size of the European squirrel, with which it also agrees approximately in the gen- 

 eral ground color of the fur. There is, however, great local variation in this 

 respect, specimens from the southern portions of the chipmunk's range being lighter 

 in color than those from the north. The distribution of this species extends from 

 Canada and Manitoba to Georgia and Western Missouri. The long-eared chip- 

 munk (T. macrotus), from California, differs from it in the much greater length of 

 its ears. 



On the other hand, the Siberian chipmunk ( T. asiaticus] , which, as we have said, 

 is common to the Old and the New World, together with some other North- American 

 species, differs by having four light-colored and five black stripes on the body. 

 The tail is also relatively longer. In the Old World, this species ranges from the 

 shores of the Sea of Okhotsk westward over the whole of Northern Asia, extending 

 in Russia as far as the river Dwina, and along the whole course of the Amur. In- 

 cluding under the specific name a large number of varieties, which some writers are 

 disposed to regard are distinct species, the Siberian chipmunk ranges in North 

 America from Lake Superior and the neighborhood of the Barren Grounds to New 

 Mexico and Arizona, and extends from the Atlantic to the Pacific seaboard. 



Chipmunks are among the commonest of North-American Rodents, 

 and their habits are consequently thoroughly well known. As those 

 of all of the species are probably nearly similar, the excellent account given by Dr. 

 Hart Merriam of the habits of the common chipmunk will suffice for all. These 

 animals are migratory, and may be very abundant in a certain district in one year, 

 while in the next comparatively few will be seen; their relative abundance being 

 dependent upon the supply of food. Chipmunks feed not only on nuts and beech 

 mast, but likewise on various kinds of corn and roots, and they are also partial to 

 the larvae of insects. When beech mast is abundant in the Adirondack mountains, 

 it may be safely predicted that swarms of chipmunks will make their appearance in 

 the autumn. In such seasons the forerunners arrive in September, while by October 



