This sullen and forbidding-looking animal, the most ravenous and ferocious that infests the more temperate regions of the earth, of many parts of which he is the terror and the scourge, is distinguished from the humble, generous, and faithful friend of man, the domestic dog, by no very remarkable or striking character; and yet there is something in his physiognomy, gait, and habit, which is at once so peculiar and so repulsive, that it would be almost impossible to confound a Wolf, however tame, with the most savage and the most wolflike of dogs. For the separation of the two species, Linn?us, as we have seen in the preceding article, had recourse to the tail; and having determined that that of the dog was uniformly curved upwards, he attributed to that of the Wolf a completely opposite direction, that is to say, a curvature inwards; assigning, at the same time, a straight or a deflected position to those of all the other animals of the group. The deflected, or down-pointing, direction is, however, equally common in the Wolf with the incurved; and this petty distinction, which has little to do with structure, and still less with habits, is hardly deserving of serious attention. More obvious and more essential differences will be found in the cast of his countenance, which derives a peculiar expression from the obliquity of his eyes; in the breadth of his head, suddenly contracting into a slender and pointed muzzle; in the size and power of his teeth, which are comparatively greater than those of any dog of equal stature; in the stiffness and want of pliability of his limbs; in his uniformly straight and pointed ears; and in a black stripe which almost constantly, and in nearly every variety of the species, occupies the front of the fore leg of the adult. His fur, which differs considerably in texture and colour, from the influence of climate and of seasons, is commonly of a grayish yellow, the shades of which are variously intermingled; as he advances in age it becomes lighter, and in high northern latitudes frequently turns completely white, a change which also takes place in many other animals inhabiting the polar regions.
The fourth Order of Birds, the Waders, are strikingly characterized by the great length of their legs, the lower part of which is entirely bare of feathers; a peculiarity which is of essential service by enabling them to stand for a long time in the water without injury to their plumage, watching for the fish and reptiles, of which the larger species, and the worms and insects, of which the smaller among them, make their usual prey.
The number at present in the Tower exceeds a hundred, varying from four to six feet in length, and differing very considerably from each other both in colour and markings.
In common with the Camels, the Llamas are distinguished from all other Ruminating animals chiefly by the absence of horns, by the structure of their feet, and by their mode of dentition, in all of which these two closely allied groups very nearly correspond with each other. In their general form there is also some similarity; but the latter are much lighter in their proportions, and far more lively and spirited in their motions. They exhibit no traces of the clumsy and unsightly humps which disfigure the backs of the former, and their necks and limbs, of greater comparative length, appear to be far less oppressed by the superincumbent weight of the head and body, which are consequently maintained in a more upright and graceful position. The principal difference in their internal structure consists in the want of that extensive appendage to the first stomach, which renders the Camel so peculiarly valuable in situations where water is with difficulty procured, by enabling him to lay in at once a sufficient stock of that indispensable necessary to supply his wants for many days. But even without this appendage the Llamas are observed to be by no means so much exposed to frequent thirst as the generality of animals, and to drink but rarely and in moderate quantity.
The Jackal, one of the greatest pests of the countries which he inhabits, is spread over nearly the whole of Asia and the north of Africa, occupying in the warmer regions of those continents the place of the Wolf, of whom in many particulars he may be considered as offering a miniature resemblance. In size he is about equal to the common fox, but he differs from that equally troublesome animal in the form of the pupils of his eyes, which correspond with those of the dog and of the wolf, in the comparative shortness of his legs and muzzle, in his less tufted and bushy tail, and in the peculiar marking of his coat. The colouring of his back and sides consists of a mixture of gray and black, which is abruptly and strikingly distinguished from the deep and uniform tawny of his shoulders, haunches, and legs: his head is nearly of the same mixed shade with the upper surface of his body, as is also the greater part of his tail, which latter, however, becomes black towards its extremity; his neck and throat are whitish, and the under surface of his body is distinguished by a paler hue.