DISTINCTIVE CHARACTERISTICS OF MAN. 



43 



is nearly in the same plane as the forehead, is peculiarly characteristic of Man ; 

 for the crania of the Chimpanzee and Orang, which approach nearest to that of 

 Man, are entirely posterior to, and not above, the face. It should be remarked 



Fig. 1. 



View of the base of the skull of Man, compared with that of the Orang Outan. 



that, in the young Ape, there is a much greater resemblance to Man in this 

 respect, than there is in the adult; for it is at the time of the second dentition, 

 that the muzzle of the Ape acquires its peculiar elongation, and consequent 

 projection in front of the forehead (Fig. 1); and the whole cast of the features 

 is altered at the same time, so that it approaches much more to that of the lower 

 Quadrumana, than would be supposed from observation of the young animal 

 only. 1 This increased projection of the muzzle, taken in connection with the 

 obliquity of the condyles, is another evidence of want of perfect adaptation to 

 the erect posture ; whilst the absence of prominence in the face of Man shows 

 that none but the erect position can be natural to him. For supposing that, 

 with a head formed and situated as at present, he were to move on all-fours, his 

 face would be brought into a plane parallel with the ground ; so that 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 then be incapacitated for receiving any other odorous emanations, than 

 those proceeding from the earth or from the body itself; and the mouth could 

 not touch the ground, without bringing the forehead and chin also into contact 

 with it. The oblique position of the condyles in the Quadrumana enables them, 

 without much difficulty, to adapt the inclination of their heads to the horizontal 

 or to the erect posture ; but the natural position, in the highest among them, is 

 unquestionably one in which the spinal column is inclined, the body being 

 partially thrown forwards, so as to rest upon the anterior extremities ; and in this 

 position, the face is directed forwards without any effort, owing to the mode in 

 which the head is obliquely articulated with the spine. 



4. The vertebral column in Man, although not absolutely straight, has its 

 curves so arranged, that, when the body is in an erect posture, a vertical line 

 from its summit would Ml exactly on the centre of its base. It increases con- 

 siderably in size in the lumbar region, so as to be altogether somewhat pyramidal 



1 None but young specimens of the Chimpanzee and Orang Outan have ever been 

 brought alive to this country ; and they have never long survived the period of their second 

 dentition. 



