MAN-LIKE APES. 21 



boar. Simultaneously with these remarkable alterations of the external structure 

 there occurs a modification of the skeleton. The skull of an aged male gorilla 

 becomes more projecting at the muzzle, and the canine teeth have almost attained 

 the length of those of lions and tigers. On the upper part of the skull, which is 

 rounded in youth, great bony crests are developed on the crown of the head and on 

 the occiput. . . . The arches above the eye-sockets are covered with wrinkled skin, 

 and the already savage and indeed revolting appearance of the old gorilla is 

 thereby increased." 



In all the Man-like Apes the number of the teeth is the same as 

 in man himself that is to say, there are on each side of both the 

 upper and lower jaws two incisors, one canine, two premolars, and three molars ; 

 the formula thus being: ^|, c\, p%, m, making a total of 32 teeth. Not only 

 do the teeth agree in number with those of man, but, with the exception of the 

 great size of the tusks, or canines, of the males, they likewise resemble them in 

 structure. We are familiar with the form of our own molar teeth, which have wide 

 crowns, with their angles rounded off and surmounted by four main tubercles set 

 somewhat obliquely to one another ; and the molars of the Man-like Apes are of the 

 same general type of structure. In the apes, however, the whole series of teeth 

 does not present the horse-shoe-like contour which is so characteristic of our own 

 teeth ; but, on the contrary, the cheek-teeth form nearly straight lines, having an 

 angulated junction with the curved line of the front teeth. 



other None of these apes possess the peculiar pouches in the cheeks 



Characteristics, occurring in many of the monkeys, and none of them have any trace 

 of a tail. Moreover, the naked patches so often found on the buttocks of the other 

 Primates are either absent or, if present, are of very small size. All of these 

 animals agree, however, with the monkeys, and thereby differ from man in the 

 great length of the arms as compared with that of the legs ; this difference being 

 very clearly indicated in our figures of the skeleton of man and the gorilla. Another 

 characteristic of the Man-like Apes shown in the figures last referred to is the great 

 breadth and flatness of the breast-bone or sternum, this being a feature in which 

 they agree with man, and differ from baboons and monkeys. Then, again, some of 

 the Man-like Apes differ from the latter and resemble man in the absence of a 

 small bone occupying a central position in the wrist, and hence known as the 

 centrale of the carpus. 



In addition to the points already mentioned, man is distinguished from the 

 Man-like Apes by the greater relative size of his brain and the portion of the skull 

 in which it is contained, as compared with the face and muzzle. His canine teeth are, 

 moreover, but little longer than the other teeth, and are thus quite unlike the huge 

 tusks of the male gorilla and orang. The great toe is also relatively longer, and is, at 

 the most, only opposable in a very limited degree to the other toes. Moreover, the 

 whole skeleton of man, as will be seen from our figure, is of a lighter and neater 

 build, with certain peculiar curvatures of the lower part of the backbone, which 

 permit of the assumption of the perfectly upright position without fatigue, and 

 without need of any support from the arms, which do not reach below the 

 middle of the thigh. Again, no ape has an ear modelled on the beautiful lines 

 of that of the human species. The naked body of man is not, however, a 



