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 feet of the Camels and of the Llamas are very different in form from those of all the other Ruminants. They are, it is true, deeply divided, like those of the latter, into two apparent toes; but cannot be said, like them, to part the hoof, for they have no real hoof, and the extremities of their protruded toes are armed only with short, thick, and crooked claws. These toes are in the Camels united posteriorly by a horny process, which is wanting in the Llamas. The teeth of both are nearly similar: they consist of six incisors in the lower jaw and two in the upper; of two canines in each; and of six molars in the upper, and five in the lower, on each side. None of the other Ruminants exhibit the least appearance of cutting teeth in the upper jaw. The nostrils of both consist externally of mere fissures in the skin, which may be opened and closed at pleasure, and which are surrounded by a naked muzzle; and their upper lip is divided into two distinct portions, which are very extensible, and capable of much separate motion.