370 



QUADRUMANA, 



of the following sketches ; fig. 259 being the skeleton of the Orang, 

 distinguishable at once by the extreme length of the arms; fig. 2GO, that 

 of the Chimpanzee. 



In the Orang, the backward position of the occipital condyles, and the 

 weight of the face, which is thus thrown forward, require a commensurate 

 development of the spinous processes of the cervical vertebrae ; added to 



259 260 



Skeleton of the Oranp. 



Skeleton of the Chimpanzee (female) . 



which, the general anterior inclination of the vertebrae themselves^ ren- 

 ders the length and robustness of these processes the more imperative. 

 In the Chimpanzee, the spinous processes, though necessarily developed, 

 are so in a less degree than in the Orang ; the anterior inclination of the 

 cervical vertebrae being less decided, and the weight of the face less op- 

 pressive. In both animals (and, indeed, in all the Simiadae) the cervical 

 region is shorter than in Man, and, therefore, better fitted for sustaining 

 the weight of the head, which preponderates anteriorly. 



In the Chimpanzee the dorsal vertebrae are thirteen, and the ribs, 

 consequently, consist of thirteen pairs ; the lumbar vertebrae are four in 

 number, being one less than in Man ; their bodies are smaller, in propor- 

 tion, than in the human subject ; but the spinous processes are compara- 

 tively longer than in the Orang. In this latter animal the number of the 

 dorsal vertebrae is twelve, as in Man ; and the number of the lumbar 



