76 



ANTHKOPOID APES. 



The skeleton of the orang has also its special 

 characteristics. We have already remarked, in 

 describing the external form of the 

 heads of these animals, that the 

 skull is high and projecting, and 

 i-etreating in its hinder part. In 

 the old male orang this part of 

 the bony structure is of smaller 

 size than in the old male gorilla. 

 The arch of the cranium is shorter 

 and rounder than in that animal 

 and in the chimpanzee. The cen- 

 tral longitudinal crest of the vertex 

 is present, but in accordance with 

 the more spherical shape of the 

 coronal part of the cranium, this 

 crest is more arched above than 

 Fig.2i.-skeietonoffoot i^ the gorilla, in which it slopes 

 ?™^Mro™e/irr gently upward to the transverse 

 Situ tan? "''dfe./; occipital crest, which rises high 

 ta"dt'o™ TmrJ^ett and peaked from the back of the 

 fifttrmototarsi' boner.'' t, head. This latter crest is indeed 

 aanges. dcvcloped in the orang, but it is 



not so high, and is more retreating. In consequence 

 of this formation, the upper posterior part of the 

 gorilla-skull appears in profile to be much more 

 abrupt and peaked than that of the orang. In the 

 latter, also, the orbital arches are not so high and 

 abrupt, and not so much detached from the rest of 

 the skull. In the orang the squamous occipital 

 portion declines abruptly in front and below, yet 

 it is generally more arched than in the gorilla. 



