SQUIRREL, a typical member of the ro dent family Sciuridce. The squirrels form the sub-family Sciurince, the members of which are of slender form and have long bushy tails. All squirrels have well-developed clavicles and the two bones of the lower leg well-developed and distinct; the premolar teeth are two above and one below, but the first upper one is small and usually deciduous; the molars, three in each jaw, broad, tuberculate and rooted; the incisor teeth are compressed and the palate broad. About 15 genera with very numerous species and sub-species are distributed through out the world except in Australia. The typical species are diurnal and strictly arboreal, but some of the ground-dwelling species are transitional to the terrestrial and burrowing marmots (subfamily Arctomyince), and some are nocturnal. They are chiefly vegetarian, but differ much in the exact nature of their food; most of them partake more or less of an animal diet and many habitually rob the nests of birds of both eggs and young. In cold and temperate climates most species hibernate more or less completely and gather stores of nuts, grains and other foods for the winter months. Some species are known to migrate occasionally in large numbers. The species are of small or moderate size, the largest equaling a cat and the smallest a mouse. Squirrels are adaptable creatures and live under a great variety of climates and conditions, the two principal cen tres of development being• regions physically so different as the Malayan Islands and North America, in the latter of which five genera and 120 species occur. The typical genus Sciurus includes species mostly of propor tionally large size with magnificent bushy tails, no cheek-pouches, the thumb rudimentary and without nail, and the first upper premolar absent or minute. Of the 75 species, approxi mately, of this genus, fully one-half are Oriental.
Few native American mammals are better known or more beloved than the gray squirrel (S. carolinensis), sometimes called the cat squirrel, and, in its melanistic phase, the black squirrel. It abounds in hardwood forests from Canada to Florida and westward to Minnesota, and in the lowlands as well as the mountainous districts. As might be expected from this
wide range, it splits into a number of distinct races. This species reaches a length of about 20 inches, of which the tail is nearly one-half and more rounded and bushy than in any other species. The eye is large, full and bright, the ears erect and pointed, but not tufted, and the color rusty gray above, more or less brown along the back and paler below. In the parks and more open parts of even large cities, wherever suitable trees supply a home and a refuge from cats and dogs, the gray squirrel has become semi-domesticated.
Its active arboreal habits and sprightly ap pearance have done much to make the squirrel the admitted type of frolicsomeness and sport. The food consists of nuts, acorns, seeds, fruits, etc., and these animals evince economic and frugal habits, in that they accumulate during the autumn a store of provisions, which is de posited in the nooks and crannies of trees. The nest and dwelling-place consists of a spherical structure formed of intertwined twigs with at tached leaves lined with leaves and bark and is generally placed in the fork of a bough, in an inaccessible situation in the top of a tall tree. Cavities in trees are similarly lined and serve as nurseries and shelters in which to hibernate. The squirrels exhibit a great attachment for their respective nests, one pair generally occupying the same tree and nest for a long period. From three to four young are produced at a birth, usually in June, the young remaining in the parent nest until the following spring. When engaged in eat ing, these animals grasp the nut or other food in their fore-paws, sitting meanwhile on their haunches and gnawing off, by aid of their powerful teeth, the hard outer coverings, and even peeling the kernel before eating it. The bushy tail of the squirrel, besides serving, when folded round the body, to retain the heat, assists through its outspread hairs in support ing the animal in its aerial leaps, a function subserved in other squirrels by special develop ments of the skin.