24 APES AND MONKEYS. 



themselves in various organic affections, although not, as has been supposed, in the 

 form of tubercular disease of the lungs. 



In all points of their structure the chimpanzees are very closely 

 related to the gorilla, although the latter is now generally referred to 

 a separate genus. Originally the chimpanzees were described under the name of 

 Troglodytes ; but since that name had been applied at an earlier date to the wrens, 

 it has now been superseded by the somewhat cumbrous, although appropriate name 

 of Anthropopithecus. This change is, however, not to be regretted on other grounds, 

 since, as the name Troglodytes means a dweller in caves, while chimpanzees are 

 purely forest animals, it is highly inappropriate to them. 



In addition to certain distinctive features in the teeth, such as the relatively 

 small size of the tusks or canines of the males, and the circumstance that the 

 upper " wisdom-tooth " is smaller than either of the two molars in advance of it, 

 chimpanzees may be readily distinguished from the gorilla by the circumstance 

 that the males are but very slightly larger than the females. Moreover, the skull 

 of the male chimpanzee is characterised by the absence of the enormous bony 

 ridges which overhang the sockets of the eyes in that of the gorilla ; while in the 

 lower jaw the length of the bony union between the two lateral branches is much 

 less than in the latter. In both these respects the chimpanzee is decidedly nearer 

 to man than is the gorilla; and a further approximation to the human type is 

 presented by the relatively shorter arms, which in the perfectly upright posture 

 only reach a short distance below the knee. The hands and feet also are longer 

 and more slender than those of the gorilla, as may be seen by comparing figs. 3-8 

 with 1 and 2 of the illustration on p. 15. Moreover, as in man, the middle finger 

 is longer than either of the others ; and although there is some degree of variation 

 in the relative length of the thumb in different individuals, as a rule this digit 

 reaches to the base of the first phalangeal joint of the index finger. The male 

 chimpanzee does not appear to exceed five feet in height when full grown, and is 

 thus considerably inferior in size to the male gorilla. 



General Dr. Hartmann remarks of the chimpanzees that, although the 



Character, arched ridges above the eyes " are not so excessively prominent as in 

 a gorilla of the same age, they are strongly developed, covered with wrinkled 

 skin, and in this case also there is a species of eyebrow, stiff and bristly, with 

 shorter hairs between. The large, wrinkled lids are furnished with thick eyelashes. 

 A general physiognomical distinction between the gorilla and the chimpanzee 

 consists in the fact that the bridge of the nose is shorter in the latter than in the 

 former. In the chimpanzee this part of the organ is depressed, yet the depression 

 is of a conical and convex form, and is covered with a network of wrinkles of 

 varying depth. In the chimpanzee the interval between the inner angle of the 

 eye and the upper lateral contour of the cartilaginous end of the nose is shorter 

 than in the gorilla. There is also some difference in the form of the nose ; it is on 

 the whole natter, the tip is less apparent, and the nostrils are not so widely opened, 

 nor so thickly padded. The external ear of the chimpanzee has, on the whole, 

 less resemblance to the human ear, and its contour is larger than that of the 

 gorilla. But this organ varies so much in individuals that it is difficult to lay 



