THE CERVICAL NERVES. *29 



to the integument of the occiput. The posterior division of the third nerve, like 

 the others, divides into an internal and external branch. The internal branch 

 passes between the Complexus and Semispinalis, and, piercing the Splenius and 

 Trapezius, supplies the skin over the latter muscle ; the external branch joins with 

 that of the posterior division of the second to supply the Splenius, Trachelo-mas- 

 toid, and Complexus. 



The third occipital nerve arises from the internal or cutaneous branch beneath 

 the Trapezius ; it then pierces that muscle, and supplies the skin on the lower and 



FIG. 495. Posterior divisions of the upper cervical nerves. 



back part of the head. It lies to the inner side of the occipitalis major, with 

 which it is connected. 



The posterior division of the suboccipital nerve and the internal branches of 

 the posterior divisions of the second and third cervical nerves are occasionally 

 joined beneath the Complexus by communicating branches. This communication 

 is described by Cruveilhier as the posterior cervical plexus. 



The posterior divisions of the fourth, fifth, sixth, seventh, and eighth cervical 

 nerves (Fig. 502) pass backward, and divide, behind the Posterior intertransverse 



