68 



THE HUMAN SPECIES 



the following order : gorilla, orang, chimpanzee and hylobates 

 bearing an increasing resemblance to the curve of the human 

 spine. 



Another peculiarity possessed by man, in centra-distinction 

 to the apes, is that the spinous processes of all human cervical 

 vertebrae branch out into two points ; this does not occur 

 in any other Primate, and in the chimpanzee only at the second 

 and third cervical vertebra (see Figs. 22 and 23). Moreover 

 in the chimpanzee, gorilla and orang, the spinal processes are 

 much longer than in man. Of phylogenetic importance is 



the perforation of the 

 transverse processes 

 of the cervical verte- 

 brae giving them the 

 appearance of two 

 processes joined to- 

 gether, of which the 

 anterior ones (from 

 the point of view 

 of comparative ana- 

 tomy) must be re- 

 garded as rudiment- 

 -Venal cavity ary cervical ribs. ' 



"Condyioid process The neck with its 



covering of flesh and 

 muscle is a further 

 characteristic attri- 

 bute of man. It 

 rises freely above the 

 shoulders, is cylindrical in the neighbourhood of the head, 

 becoming broader towards the thorax, and is curved, back and 

 front, where it joins the head. It forms another distinction 

 between man and the anthropoids, for in the latter the neck 

 is by no means free, the head hangs forward on the breast, 

 sunk between the shoulders as in a human being deformed 

 by rickets. The ligamentum nuchas is considerably less de- 

 veloped in man than in the other mammals. Schwalbe has 

 found that in the cervical ligament of the ruminants the 

 elastic filaments are arranged like cords inside which they 



Odontoid peg 



Condyloid process 

 Venal cavity 



Condyloid process 



FIG. 22. Episterpheus (front view). 



FIG. 23. Fifth cervical vertebra (viewed from 

 underneath). 



