UNDER VIEW OF WOLF’S SKULL.
The form of the teeth, as well as their number, comes much nearer to that of an ordinary Mammal, or is much less specially carnivorous than in the Cats. The incisors are proportionally larger than in our first section; their crowns are distinctly divided into three cusps—a large central and two small lateral ones; and the outermost incisors of the upper jaw approach tolerably nearly in shape and size to the canines, being nearly half as long as the latter, and having almost lost their lateral cusps. The canines have much about the same form and relative size as in the Cat, as also have the premolars, except that the first of these, though smaller than its successor, is not so markedly so as in the Cats, while, on the other hand, the last (the carnassial) is proportionally larger.
TEETH OF WOLF.
The letters have the same significance as in the [figure of the Lion’s teeth on p. 13], except h, the “heel” of the lower carnassial.
But in the molars, or at least in all but the lower carnassial, we find something quite different, namely, an interesting approximation to the semi-herbivorous type of dentition of the Bears. Both molars in the upper jaw, and the two last in the lower, have become bonâ fide “grinders.” The scissor-like cutting edge has disappeared, and in place of it we have a hard crushing surface, raised into four cusps—two large external and two smaller internal ones. This has relation, of course, to the mixed character of the Dog’s food. The sectorial molar of the lower jaw still, however, retains its distinctive characters; its crown has much the same shape as in the Cat, but in addition possesses an extra lobe, in the shape of a large heel-like process projecting from its hinder border, and formed by a modification of its posterior cusp.
SKELETON OF WOLF.
The Dog family have, as a rule, longish legs. They walk on the tip of their toes, like the Cats; but unlike the latter, their claws are not retractile. Curious to relate, however, the elastic ligament by which the drawing back of the feline claw is effected is present, but in so feeble a condition as to be quite incapable of antagonising the great flexor muscles.
In consequence of this, the paw of a Dog is by no means such a perfect weapon as that of a Cat; and, as a matter of fact, the Dogs are distinguished from the Cats by their habit of always attacking the prey at once with their teeth, and never beginning the attack with a blow of the paw.