77//1 HEAD AND NECK. 



59 



off in the neck (i) the superior laryngeal nerve to the larynx ; (2) the cervical 

 cardiac branches ; (3) the pharyngeal branches ; (4) the recurrent laryngeal 

 nerve. 



For the present remember this : The pneumogastric supplies the organs of 

 voice and respiration with motion and sensation ; the organs of circulation and 

 digestion with motion only. 



The internal carotid artery on each side begins at the bifurcation of the 

 common carotid. Find this bifurcation and see whether it is opposite the thyroid 

 cartilage or the hyoid bone. The internal carotid has four stages : 



i. The ccrrical to the base of the skull, from the bifurcation. 



Fiu. 31. VESSELS ANIJ NERVES OF THE HEAD AND NECK. 



I. Subclavian artery. 2. Subclavian vein. 3, 3. Common carotid artery. 4. internal jugular vein. 

 5. Anterior jugular vein. 6. Omo-hyoid muscle. 7. Sterno-hyoid muscle. 8. Trunk of pneumo- 

 gastric nerve. 9. Hypo-glossal nerve. 10. Its terminal portion. if. Its descending branch. 

 12. Internal descending branch of cervical plexus. 13. Plexus formed by last two branches. 

 14. External carotid artery. 15. Superior thyroid artery and vein. 16. Lingual and facial arteries. 

 17. Facial artery and vein. 18. Occipital artery. 19. Anterior branches of the first four cervical 

 nerves. 20. Superior laryngeal nerve. 



2. The petrosal in the carotid canal in the petrosa. 



3. The cavernous in the cavernous sinus on the lingula. 



4. The cci'cbral at the base of the brain in the cranium. 



The cervical stage gives off no branches in the neck. The function of this 

 artery is to take blood to the brain, eye, and nose. It assists the vertebral in 

 forming the circle of Willis, by which circle the brain receives all its blood. 

 Blood returns from the brain by the internal jugular vein. 



External Carotid Artery. This vessel begins at the bifurcation of the 

 common carotid artery just mentioned. In some tubercular cases you will find 



