THE CHIMPANZEES AND ORANGS. 97 



minal tuberosities directed outwards and a little backwards. The body is deeper behind 

 in proportion to its breadth than in the Orang, and the vertical concavity equals the 

 transverse convexity of that articular surface : the neural canal is less contracted above : 

 the anterior zygapophyses are larger and better defined. In all these respects the 

 Chimpanzee, like the Gorilla, approaches nearer to Man than the Orang does. 



In the third cervical vertebra of the Chimpanzee the fore part of the bases of the neur- 

 apophyses are produced forwards beyond the centrum and complete the transverse con- 

 cavity for the reception of the backwardly-produced body of the axis. This surface is 

 deeper in proportion to its breadth than in the Orang, and in this respect approaches 

 nearer to that of Man. The vertebral arterial foramina are larger, the neural canal wider, 

 and the anterior zygapophyses better defined, than in the Orang. The body of the ver- 

 tebra is longer in proportion to its breadth than in the Orang, and the vertical concavity 

 of the hinder surface is deeper. The costal portion of the transverse process is com- 

 pressed and slightly produced downwards, forming an obtuse angle distinct from the more 

 acute diapophysis which is prolonged outwards and backwards. The neural spine is sub- 

 trihedral, slender, obtusely pointed, and its base is coextensive with the neural canal. 



The fourth cervical vertebra of the Chimpanzee, in the greater depth and minor breadth 

 of the body, and in the larger relative size of the neural canal and of the vertebral arterial 

 foramina, repeats the same differences from that of the Orang, and the same resemblances 

 to that in Man, as the foregoing vertebra does. The neurapophyses still form the 

 sides of the anterior concavity of the body. The costal ridge is equally distinct ; the 

 diapophysis is longer and the neural spine is a little longer than in the preceding 



vertebra. 



The same differences, as compared with the fifth cervical in the Orang, are repeated 

 in this vertebra of the Chimpanzee. The costal portion of the transverse process is 

 more produced. The neural spine is both longer and stronger. The diapophyses are 



somewhat less. 



The sixth cervical differs from the foregoing in a slight increase of breadth and pro- 

 minenceof the pleurapophysis, and in a diminution of the drapophysis : the centrum is 

 more expanded posteriorly: the neural spine is longer and thicker than in the Orang, 

 but is proportionally less developed than in the Gorilla. 



In the seventh cervical vertebra the costal portions of the transverse process are 

 reduced to an osseous filament, which completes the lower boundary of the vertebral 

 arterial canal. The diapophysis is much longer and thicker than in the sixth. The 

 transverse extent of the centrum continues to increase, as also the antero-posterior 

 breadth of the neurapophyses. The neural spine increases in breadth and slightly in 



len^'th. 



fn the atlas of the male Australian (PI. XXXIII. figs. 8 & 9) there is a tubercle from 

 the fore part of the hypapophysis (hy) representing the body, and a rough surface on 

 the back part of the neural arch (n) in place of a spine. The body is longer and deeper in 



VOL. IV. PART IV. ^ 



