50 THE STRUCTURE OF MAN 



essential importance for us here is the fact that the skull of Man 

 and all Vertebrates is constructed on a common plan (cf. A and 

 B, Fig. 31). 



The fact that this ground plan is not so evident in the skull 

 of the higher Vertebrata and Man as in that of the lower Verte- 

 brates, is due to the progressive modification which the former have 





FIG. 32. SKULL OF IMMANUEL KANT. (After C. von Kupffer.) 

 (The great size of the cranium is a noteworthy feature. ) 



undergone ; and the final result has been that the human skull 

 differs markedly not only from that of the lower Vertebrata, but 

 also from that of the Anthropoid Apes, which in the rest of their 

 skeleton agree so closely with Man. It will, therefore, be interest- 

 ing to examine the two latter types of skull, in order to determine 

 and, when possible, explain the differences between them. 



On mere superficial examination, the proportionate difference 

 in size between the cranium and the face of the two is most 

 striking. In Man (Fig. 32) the cranium is a smooth and imposing 



