We have seen that the aye-aye may be considered as connecting the Quadrumana with the Bradypes, on the one hand, and the squirrels on the other. These two groups, however, exhibit a very striking contrast between their habits and disposition; and since to animals of the former the name has been given of “Sloths,” the latter might justly be designated “the Active.” If there exist, indeed, any animals for whom movement is a vital necessity, these, assuredly, are the squirrels. They climb trees with great agility, and leap from one branch to another with a marvellous vigour and precision. On the ground, they trot rather than run. They are essentially graminivorous and frugivorous; nuts, fruits, seeds, the young stems of trees, forming their chief nourishment, though at times they plunder birds’ nests, and regale themselves with the eggs or even the “callow brood.”
The Squirrel (Sciurus) belongs to the family Sciuridæ, in the order Rodentia. Their special characteristics may be enumerated as a long bushy tail, generally carried curved over the body, whence the Greek name Skiouros (σκια, a shade, and ουρα, a tail), fore-paws furnished with four toes, which have curved claws, and a tubercular thumb; long hind-legs, the feet provided with five toes; two incisors in each jaw; and four molar teeth on each side of each jaw, simple, with tuberculous crowns, and a fifth in front of the upper jaw, which soon falls out. The squirrel’s fur, thick and soft, is of a bright reddish-brown colour, more or less varied with gray; with a snow-white belly and breast, and a tail brown, or almost black. The ears are ornamented with long tufts of hair. The eyes, directed laterally, are black and lively, shining with subdued mischief; the legs are short and muscular; and when on the ground the animal moves by a succession of leaps, the tail being undulating and extended. He lives constantly in the forest, selecting a particular tree, where he builds his nest, either in a hollow of the trunk or among the branches. In the latter case he builds himself a sort of cabin, with twigs and stems, artfully concealed beneath a covering of moss and fragments of bark. There he lives “by his ain fireside,” in the company of his mate and their young ones, collecting an abundant magazine of nuts and acorns for their winter provision. In the spring and summer he loves to gambol among the leafy boughs, climbing up and down the forest trees, and uttering a short quick stuccato cry, like the sound which we produce by clacking the tongue against the palate. If you attempt to seize him, he bites sharply, and scratches like a cat. He is nevertheless easily tamed, and his engaging manners, his amusing gambols, and constant liveliness, make him a great favourite among our “domestic pets.” He soon grows accustomed to his cage, and after a brief interval of liberty returns to it of his own accord.
The Common Squirrel (Sciurus vulgaris) is found all over Europe, North America, and the Northern and Temperate regions of Asia. He is about eight inches and a-half in length, without the tail, which measures fully six inches long. In Lapland and Sweden his colour changes to gray in the winter season; in the snowy wastes of Siberia, he is frequently seen of a pure white.
The only other European species is the Alpine Squirrel (Sciurus Alpinus), a native of the Alps and Pyrenees, of a deep brown colour, speckled with yellowish-white.
To North America belongs the Gray Squirrel (Sciurus Carolinensis), where he enjoys his free and sportive life in the great forests of hickory, oak, maple, and chestnut. His whole length, including the tail, is about two feet. As he forays plentifully among the corn-fields, the inhabitants regard him as a scourge, and wage deadly war against him. Like the lemming, he migrates about autumn, in immense hosts; advancing in a straight course, which no obstacle is permitted to interrupt, and spreading desolation, like the course of an invading army.
The large species of the Fox Squirrel (Sciurus vulpinus) belongs exclusively to the “murmurous pine-woods” of South America. The Cat Squirrel (Sciurus cinereus) is remarkable for the exquisite fineness of his fur. In the neighbourhood of Hudson’s Bay dwells the Red or Hudson’s Bay Squirrel (Sciurus Hudsonius), marked along the middle of the back by a ferruginous line from head to tail, with the belly of a pale ash-colour, mottled with black.