136 A MANUAL OF ANATOMY. 



It appears in the dissection of the posterior region of the 

 neck, under the complexus and upon the semispinalis ; its 

 course is vertically upward to anastomose at the suboccip- 

 ital triangle with the deep branch (continuation) of the 

 princeps cervicis of the occipital. The artery in its course 

 enters into anastomoses with branches of the vertebral. 



The Deep Cervical Vein (Prof undo, Cervicis Vein). 



This begins in the suboccipital triangle by the confluence 

 of smaller veins from the surrounding parts. It descends 

 along the course of the deep cervical artery, and opens into 

 the innominate or vertebral veins. 



The Vertebral Vein. See page 1 1 1 . 



In the suboccipital triangle the deep cervical and verte- 

 bral veins freely communicate. 



The vertebral receives tributaries from within the spinal 

 canal, the vertebrae, and muscles. 



The Suboccipital Nerve. 



The posterior division of the first cervical nerve passes 

 backward between the vertebral artery and the posterior 

 arch of the atlas, then through the suboccipital triangle to 

 the deep surface of the complexus muscle. 



It supplies the muscles forming the triangle, the rectus 

 capitis posticus minor, the complexus, and sends a twig to 

 the great occipital nerve. 



The Deep Cervical Fascia. 



The deep cervical fascia consists of the membranous 

 sheaths of muscles, the covering of glands (capsules), the 

 firm supporting encasement of vessels and the thinner ones 

 of nerves, and the connecting processes (or ligaments) 

 which join the detached to the fixed parts of the head and 

 neck. 



