THE GREAT CHIMPANZEE. 385 



found in Borneo ;—tliat, besides the Pithecus Wurmbii and the variety or species called 

 Pithecus Abelii, a smaller and more anthropoid Orang (Pithecus Mono), with proportions 

 of the incisor and molar teeth as contrasted with the larger species not hitherto known 

 to characterize mere varieties of Ajjc, also exists in Borneo, and is apparently peculiar 

 to that island ; — and, notwithstanding the carnassial and baboon-like features are less 

 strongly developed in the Pithecus Morio than in its larger congener, that the characters 

 of the Orang-outang in the ' RSgne Animal' of Cuvier apply only to the immature state 

 of any of the species of Pithecus now known. The same essential correction of the 

 current ideas respecting the facial angle and the proportions of the cranium and face 

 was made with respect to the Chimpanzee, and the true adult characters of the skeleton 

 and dentition as manifested in the female of the Troglodytes nirjer were described and 

 illustrated ; and it was shown by these that, although the departure from the bimanous 

 type is not so great in the Troglodytes niger as in the Pithecus Wurmbii, it is quite equal 

 to that in the Pithecus Morio. 



§2.0/ the Skull and Dentition of the adult male Troglodytes niger. 



There remained then to be determined the true adult characters of the male of the 

 Troglodytes niger, and especially those aftbrded by the bones and teeth. In general 

 stature, the male of this species, when it has acquired its second or mature dentition, 

 does not exceed the female by more than two inches, and does not attain a greater 

 height, mea-sured from the sole of the heel to the vertex in a straight line, than 4 feet, 

 the height of the mature female being 3 feet 10 inches; but it presents a greater 

 proportional breadth of chest and shoulders, and greater strength of arm. It is charac- 

 terized, however, by the same sexual superiority in the size of the canines as is mani- 

 fested in the genus Orang (Pithecus). 



The following are the general characters of the mature dentition of the adult male 

 Chimpanzee (Troglodytes niger) : — 



This dentition, though in all its principal characters strictly quadruraanous, yet, in 

 the minor particulars in which it differs from the dentition of the Orang, approaches 

 nearer the human type. In the upper jaw the middle incisors (PI. LIX. i i) are smaller, 

 the lateral ones (ib. i 2) larger than those of the Orang*; they are thus more nearly 

 equal to each other ; nevertheless the proportional superiority of the middle pair is greater 

 than in Man, and the proportional size of the four incisors both to the entire skull and 

 to the other teeth is considerably greater. Each incisor has a prominent posterior basal 

 ridge, and the outer angle of the lateral incisors is rounded off as in the Orang. The 

 diastema between the incisors and the canine on each side is as well-marked in the male 

 Chimpanzee as in the male Orangf. The crown of the canine (ib. c), passing outside 



* Compare PI. LIX. with PI. XXXI. (Pith. Wurmbii) and PI. XXXIII. (Pith. Morio), in vol. ii. Zool. Trans, 

 t Compare PI. LVIII. witli PI. XXXII. (Pith. Wurmbii) in vol. ii. Zool. Trans. 



