120 



THE SKELETON. 



broad and strong, especially their anterior extremities, which coalesce with the 

 sides of the body and the root of the odontoid process. The laminae are thick 

 and strong, and the spinal foramen very large. The superior articular surfaces 



Fig. 70. 2d Cervical Vertebra, or Axis. 

 Odontoid Pros 



Rcniffl Surf.fr CAee'A Li'y^ 

 Artic. Swrf.fer 



Spin. Froe, 



Artie. Surf, for Atlas 



Body 



are sound, slightly convex, directed upwards and outwards, and are peculiar in 

 being supported on the body, pedicles, and transverse processes. The inferior 



articular surfaces have the same 



Fig. 71. 7th Cervical Vertebra, or Vertebra Pro- direction as those of the other 

 minenSt cervical vertebrae. The superior 



intervertebral notches are very 

 shallow, and lie behind the arti- 

 cular processes; the inferior in 

 front of them, as in the other 

 cervical vertebras. The trans- 

 verse processes are very small, 

 not bifid, and perforated by the 

 vertebral foramen, or foramen 

 for the vertebral artery, which is 

 directed obliquely upwards and 

 outwards. The spinous process 

 is of large size, very strong, 

 deeply channelled on its under 

 surface, and presents a bifid tu- 

 bercular extremity for the attach- 

 ment of muscles, which serve to 

 rotate the head upon the spine. 



Seventh Cervical (Fig. 71). The 

 most distinctive character of this 

 vertebra is the existence of a very 



long and prominent spinous process; hence the name "Vertebra prominens." 

 This process is thick, nearly horizontal in direction, not bifurcated, and has 

 attached to it the ligamentum nuchae. The transverse process is usually of 

 large size, especially its posterior root; its upper surface has usually a shallow 

 groove, and it seldom presents more than a trace of bifurcation at its extremity. 

 The vertebral foramen is sometimes as large as in the other cervical vertebrae, 

 usually smaller, on one or both sides, and sometimes wanting. On the left side 

 it occasionally gives passage to the vertebral artery; more frequently the ver- 

 tebral vein traverses it on both sides; but the usual arrangement is for both 

 artery and vein to pass through the foramen in the transverse process of the 

 sixth cervical. 



