great increase in length, so that it projects much more beyond the forehead. The whole cast of the features is altered at the same time; so that it approaches more nearly to that of the Baboons, and other inferior Quadrumana, than would be supposed from observation of the young animal only. This increased projection of the muzzle is an evidence of want of perfect adaptation to the erect posture; whilst the absence of it in Man shows that no other position is natural to him. Supposing that, with a head formed as at present, he were to move on all-fours, so that his face would be brought into the same plane with the ground,—as painful an effort would be required to examine with the eyes an object placed in front of the body, as is now necessary to keep the eyes fixed on the zenith; the nose would be unable to perceive any other odours than those which proceed from the earth, or from the body itself, their aperture being directed backwards; and the mouth could not touch the ground to take up food (which it must have done if the anterior limbs were used for support), without bringing the forehead and chin also into contact with it.

131. The vertebral column in Man, though not absolutely straight, has its curves so arranged, that, when the body is in an erect posture, a vertical line from its summit would fall exactly on the centre of its base. It increases considerably in size in the lumbar region, so as to be altogether somewhat pyramidal in form; and it is set upon the sacrum by a very broad base. The iliac bones are widely expanded, so that the whole pelvis is very broad; in this manner the hip-joints are thrown farther apart from each other, so as to give a firmer basis of support. The breadth of this is still further increased by the oblique position of the neck of the thigh bone. The position of this bone, in which its head is most secure in its deep socket, is when it is supporting the body in a vertical position,—that is, when it has the same direction with the spinal column. In the Chimpanzee and Orang, on the other hand, the most secure position is when the spinal column is bent forwards at an angle upon it; in several other Mammals, as the Elephant, the spinal column forms a right angle with the thigh bone; and in many others, as the Horse, Ox, &c., the angle is less than a right angle, the thigh-bone

being drawn up (as it were) towards it. The formation of the knee-joint of Man, again, is such, that the whole weight of the body falls directly upon the head of the tibia, when the joint is in the firmest position in which it can be placed; and this is not the case even with the Apes, that approach nearest to him in form. The conformation of the foot of Man is, of itself, an indisputable evidence that the erect position is natural to him. It is proportionally larger, broader, and stronger, than the foot of any other Mammal, save the Kangaroo. The sole of the foot is concave, a sort of arch being formed by the bones and ligaments of which it is composed; and the weight of the body is thrown upon the summit of this arch, by the mode in which the anklejoint is constructed. This is far from being the case with the semi-erect Apes; for they have the os calcis, or bone of the heel, small, straight, and more or less raised from the ground, which they touch, when standing erect, with the outer side of the foot only, so that they cannot stand at all firmly on their posterior limbs only. In animals more remote from Man, the os calcis is brought still more into the line of the tibia, (Fig. 51); and the foot being more lengthened and narrowed, the extremities of the toes alone come in contact with the ground. Hence Man is the only species of Mammal, that can stand upon one leg without other support; the Kangaroo, when using one of its hind legs to kick backwards at its pursuers, keeps itself erect on the other by means of its powerful tail.

132. The modification of the hind-foot of the Apes, which renders it unable to support the body firmly in the erect posture, is exactly that which gives it somewhat of the character of the hand; and consequently the hand of Man, in which this modification is still more completely effected, is still less adapted for the support of the body. The disproportion in length, between the anterior and posterior extremities, is another indication of the natural erectness of his posture. His legs are longer, relatively to the size of his trunk, than those of any other Mammal, except the Kangaroo; and his arms are shorter in proportion, than are those of the Apes that approach him most closely. For whilst his hands only reach the middle of the thighs, they

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hang in the Chimpanzee on a level with the knees, and in the Orang they descend to the ankles; hence, when the bodies of the latter are thrown but a little forwards, their anterior extremities are ready to support them in this inclined position. Now it is evident that progression on all-fours would be rendered excessively inconvenient, in consequence of this disproportion. Either Man would be obliged to rest on his knees, with his thighs bent towards the trunk, and his legs and feet entirely useless; or he must elevate his trunk on the extremities of his toes, throwing his head downwards, and making the pelvis much higher than the shoulders. In either case, the only useful movement would be at the hip; and the knee and ankle joints would be of little or no use to him. Many other facts might be brought together, in addition to these, in support of the conclusion (which scarcely admits of being reasonably disputed), that the erect attitude, and biped progression, are natural to Man; and we must regard as in great degree fabulous all those histories of supposed wild men, who, it has been said, were found in woods, dumb, hairy, and crawling upon all-fours. The most elaborate investigation of the structure of the highest Apes, and the fullest acquaintance with their habits, concur in proving, that their movements are not easy or agile, unless they employ all their limbs for the support of their bodies.

133. Thus, then, although the order Bimana cannot be separated from the Quadrumana, by any single obvious point of structure, like that which characterises the Cetacea, Cheiroptera, Rodentia, or Ruminantia, it is really as far removed by the minuter, but not less important, modifications which have been detailed. A few others will now be noticed. With one exception (the fossil genus Anoplotherium, which is allied to the Tapir tribe) Man is distinguished from all other animals, by the equality in the length of all his teeth, and by their being closely ranged together in both jaws. Even the Apes have the canine teeth (especially in adult age) longer than the others; and an interval in the line of teeth in each side of the jaw, to receive the canines of the opposite jaw. The vertical position of the Human teeth, on which one of the most characteristic features

of the Human face, the prominent chin,-depends, is also quite peculiar to him; and is intimately connected both with his erect attitude, and with the perfection of the hands, by which the food is divided and conveyed to the mouth. He has no occasion for that protrusion of the muzzle and lips, which, in animals that seize their food with the mouth only, is required to prevent the whole face from coming into contact with it.-The absence of any weapons of offence, and of any direct means of defence, are remarkable characteristics of Man, and distinguish him from other animals. On those, to whom Nature has denied weapons of attack, she has bestowed the means either of passive defence, of concealment, or of flight. Yet Man, by his superior reason, has not only been enabled to resist the attacks of other animals, but even to bring them under subjection to himself. His intellect can scarcely suggest the mechanism, which his hands cannot frame; and he has devised and constructed arms more powerful than those which any other creature wields, and defences so secure as to defy the assaults of all but his fellow men. As we might expect from his far higher intelligence, the brain of Man far exceeds that of the most elevated Quadrumana in size; and at least equally surpasses it in the complexity and high development of its internal parts, and in the depth and number of its convolutions.

134. Man cannot be regarded as distinguished from Mammalia, however, either by acuteness of sensibility, or by muscular power. His swiftness in running, and agility in leaping, are inferior to that of other animals of his size,-the full-grown Orang for example. The smallness of his face, compared with the remainder of the skull, shows that the portion of the nervous system distributed to the organs of sense is proportionally less developed in him than it is in most other animals; and we find that he is surpassed by many among them in the acuteness of his sensibility to light, sound, &c. ; though he stands alone in the power of comparing his sensations, and of drawing conclusions from them. Moreover, although none of his senses are very acute in his natural state, they are all capable (as is also his swiftness of foot) of being much improved by practice, when