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[182] 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