290 THE VASCULAR SYSTEMS 



(c) Through the parietal foramen, from the superior longitu- 

 dinal to the veins of the scalp. 



(d) Through a foramen in the external occipital protuberance 

 to the occipital veins. 



(e) Through the foramen ovale, from the cavernous to the 

 pterygoid plexus. 



(/) Through the foramen lacerum medium, from the cavernous 

 sinus to the pharyngeal plexus. 



(g) Through the carotid canal, a small plexus from the 

 cavernous sinus to the internal jugular. 



(h) Through the anterior condylar foramen, a plexus from the 

 occipital sinus to the deep cervical veins. 



THE VEINS OF THE UPPER EXTREMITY 



The superficial veins commence from a plexus on the dorsum 

 of the hand mostly, but to some extent from the palm. They 

 comprise the following: 



The ulnar, anterior and yotfrrtor, uniting above in the common 

 ulnar. 



The radial vein is situated on the outer side, and the median 

 ascends mesially, receives a deep median vein, and divides at 

 the bend of the elbow into the median basilic and median 

 cephalic. 



The median basilic joins the common ulnar to form the basilic. 

 The bicipital fascia separates it from the brachial artery. 



The median cephalic crosses the external cutaneous nerve, 

 and joins the radial to form the cephalic. 



The basilic runs along the inner side of the biceps, pierces the 

 fascia, and is continued upward into the axillary vein. 



The cephalic runs along the outer side of the biceps, and be- 

 tween the pectoralis major and deltoid, piercing the costocora- 

 coid membrane to join the axillary vein below the clavicle. 



The deep veins of the upper extremity are the venae comites. 

 They run one on each side of its artery from the digital to the 

 brachial arteries. The venae comites of the latter vessel, at 

 the lower border of the subscapularis muscle, empty into the 

 axillary vein. 



The axillary vein begins where the vense comites of the brachial 

 artery and the basilic vein unite. It runs internal to the artery, 



