xxiv. 8 SKULL AND JAWS 637 



finger'). In lower primates the digits of the ulnar side are relatively 

 much longer. Apart from proportions and skeletal features the human 

 hand also has a very well developed sensory supply, which is essential 

 for its use as a handling organ. 



Notharctus 



Fig. 412. Foot skeleton of a series of Primates. 

 (After W. K. Gregory.) 



8. The skull and jaws of man 



Comparisons between the skulls of apes and men have attracted 

 special attention because so many of the finds of early human types 

 have been of skulls (Fig. 413). The differences are mainly referable to 

 changes in the brain, dentition, and method of balancing the head upon 



