VERTEBRATA 



195 



teeth in all. In the apes of the Old World the tail is never 

 prehensile, and is sometimes wanting; the nostrils are 



FIG. 188. Skull of orang-outang (Simia FIG. 189. Skull of chimpanzee (Anthro~ 

 satyrus}. popithecus troglodytes). 



close together ; both thumbs and great toes are opposa- 

 ble ; and the teeth, though numbering the same as man's, 



FIG. 190. Female orang-outang (from photograph). Borneo. 



are uneven (the incisors being prominent, and the canines 

 large), and the series is interrupted by a gap on one side 



