SQUIRRELS. 



77 



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 

 numerous varieties, is distinguished by having two white stripes, 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 general ground-colour of the fur. There is, however, great local variation in 

 this respect, specimens from the southern portions of the chipmunks' range being 

 lighter in colour than those from the north. The distribution of this species 

 extends from Canada and Manitoba to Georgia and Western Missouri. The long- 

 eared chipmunk (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-coloured 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. Including under the specific name a large number of varieties, which some 

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

 North America from Lake Superior and the neighbourhood 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 the woods are alive with these creatures. " Finding 

 an abundance of food," writes Dr. Merriam, " they immediately establish themselves 

 for the winter, and begin at once to hoard up large stores. They are the least 

 hardy of our squirrels, commonly going into winter-quarters before the middle of 

 November, and rarely appearing again in any numbers till the warm sun, in March 

 or April, has caused plots of bare ground to appear between the snow-banks. 

 Early thaws sometimes bring them out in February; and after having once 

 emerged they often make little excursions over the snow during pleasant days, 

 though the temperature may be several degrees below freezing. In running from 

 tree to tree, even when not pursued, the length of their bound varies from twenty- 

 five to thirty-four inches a long leap for so small an animal." They commonly 



