ANATOMICAL STRUCTURE OF ANTHROPOID APES. 69 



many points of resemblance to that of the gorilla, 

 while it differs in certain particulars from the 

 structure of other anthropoids. And first, the size 

 of the skeleton is smaller than that of the gorilla, 

 which is in agreement with the smaller relative size 

 of the body of the chimpanzee. 



Fig. 18.— Skull of an aged male chimpanzee. 



We must begin with a general view of the skull 

 of the chimpanzee. In both sexes the frontal 

 regions are smaller, while the coronal region is more 

 rounded than in the gorilla. The high bony crests 

 and prominent supra-orbital arches are wanting in 

 the chimpanzee ; the peculiar character of the bony 

 ridges, projecting like tubes from the other parts 

 of the skull, is less marked, and they belong more 

 directly to the frontal region (see Pig. 18). The 

 bony bridge of the nose is more concave in the 



