THE INTERNAL CAROTID ARTERY 



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scapular vessels, and traversing its upper angle in the same direction, the trans- 

 versalis colli artery and vein. The external jugular vein runs vertically downward 

 behind the posterior border of the Sternjmastoid muscle, to terminate in the 

 subclavian vein; it receives the transverse cervical and suprascapular veins, which 

 occasionally form a plexus in front of the artery, and a small vein which crosses 

 the clavicle from the cephalic. The small nerve to the Subclavius muscle also 

 crosses this triangle about its middle. A lymph node is also found in the space. 

 Its floor is formed by the first rib with the first digitation of the Serratus magnus. 



1st Aortic 



FIG. 447. The internal carotid and vertebral arteries. Right side. 



The Internal Carotid Artery (A. Carotis Interna). 



The internal carotid artery supplies the anterior part of the brain, the eye and 

 its appendages, and sends branches to the forehead and nose. Its size in the 



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