VERTEBRM 29 



two centres, distinct from each other and from the body of the vertebra. After 

 the axis, the cervical vertebrae diminish in length and increase in thickness ; 

 while the obliquity of their articular processes becomes more pronounced the 

 more distant they are from that vertebra. 



Third, fourth, and fifth.— Each, of these has, at its transverse processes, two 

 prolongations — one anterior, the other posterior. The inferior face of their bodies 



AXIS AND SIXTH CKRVICAL OF THE HORSE AND ASS. 



A. Axis of the Horse. 1, spinous process ; 2, transverse process ; 3, odontoid process ; 

 4, lateral articular facet. 



B. Axis of the Ass. Same numbers and same signification. 



a', Sixth cervical vertebra of the Horse. 1, Articular head ; 2, posterior articular process ; 

 3. articular cavitv ; 4, posterior prolongation of the transverse process : 5, anterior ditto. 

 b', Sixth cervical vertebra of the Ass. Same numbers and same signification. 



exhibits a median spine terminated posteriorly by a tubercle, which gradually 

 increases in volimie from the third to the fifth vertebra. 



The third presents, between its anterior and posterior articular processes, an 

 almost complete gap ; if its anterior extremity be placed on a horizontal plane, 

 it will touch that plane by its articular and transverse processes and its head. 



