In internal and anatomical structure, on which modern naturalists are agreed that the greatest reliance ought to be placed in the distinction of closely approximating species, there is in the various races of Wolves no deviation from the common type of sufficient importance to warrant their separation from each other; neither does their outward form, excepting only in size and in the comparative measurement of parts, differ in any remarkable degree. In colour it is true that the most striking variations are observable, their hair exhibiting almost every intermediate shade between the opposite extremes of black and white. But it must be obvious that on this character, taken by itself, it would be absurd to insist as a ground of specific distinction, when we reflect on the influence which climate and other external accidents must necessarily exercise on animals so extensively dispersed, and so variously circumstanced. There are, however, strong grounds for believing that the fine pair of animals, whose portraits are prefixed to the present article, exhibit real and substantial marks of distinction of sufficient value to sanction their separation from the other species. Considerably larger and more robust than the Common Wolf, and differing greatly in the expression of their physiognomy, neither in figure nor in countenance are they remarkable for that starved and gaunt appearance which is the common and well known attribute of the latter. In fact, they have altogether a more fierce and formidable, but at the same time a more noble and less sinister, aspect. Their hair, which is of considerable length, especially along the middle of the back and shoulders, where it forms a sort of indistinct and scattered mane, is mottled with various shades of black, gray, and white, giving to the whole animal that dark and clouded colour which constitutes one of its most peculiar and striking characteristics. The colouring, which, on the upper parts of the body, is deep black, becomes somewhat lighter on the sides, and assumes a yet lighter shade beneath: the chin and angles of the mouth are nearly white; the gray tinge predominating over the darker shades in various other parts, but by no means in so regular a manner as to merit a particular description. The ears are remarkably short; and the tail is also somewhat shorter in proportion than that of the common wolf, not reaching, in its solid form, beneath the posterior bend (which in all these animals is formed by the heel) of the hind legs.