AXILLARY VEIN. 377 



of the arm to its upper third ; it then enters the groove between the 

 pectoralis major and deltoid muscles, where it is in relation with the 

 descending branch of the thoracico-acromialis artery, and terminates 

 beneath the clavicle in the subclavian vein. A large communicating 

 branch sometimes crosses the clavicle between the external jugular 

 and this vein, which gives it the appearance of being derived directly 

 from the head hence its appellation. 



The Median vein is intermediate between the anterior ulnar and 

 radial vein ; it collects the blood from the anterior aspect of the fore- 

 arm, communicating with the two preceding. At the bend of the 

 elbow it receives a branch from the deep veins, and divides into two 

 branches, the median cephalic and median basilic. 



The Median cephalic vein, generally the smaller of the two, passes 

 obliquely -outwards, in the groove between the biceps and supinator 

 longus, to join the cephalic vein. The branches of the external cuta- 

 neous nerve pass behind it. 



The Median basilic vein passes obliquely inwards, in the groove 

 between the biceps and pronator radii teres, and terminates in the 

 basilic vein. This vein is crossed by one or two filaments of the in- 

 ternal cutaneous nerve, and is separated from the brachial artery by 

 the aponeurotic slip given off by the tendon of the biceps. 



AXILLARY VEIN. 



The axillary vein is formed by the union of the venae comites of the 

 brachial artery with the basilic vein. It lies in front of the artery, 

 and receives numerous branches from the collateral veins of the 

 branches of the axillary artery ; and, at the lower border of the first 

 rib, becomes the subclavian vein. 



SUBCLAVIAN VEIN. 



The subclavian vein crosses over the first rib and beneath the 

 clavicle, and unites with the internal jugular vein to form the vena 

 innorninata. It lies at first in front of the subclavian artery, and then 

 in front of the scalenus anticus, which separates it from that A r essel. 

 The phrenic and pneumogastric nerves pass between the artery and 

 vein. The veins opening into the subclavian are the cephalic below 

 the clavicle, and the external and anterior jugulars above ; occasionally 

 some small veins from the neighbouring parts also terminate in it. 



VEINS OF THE LOWER EXTREMITY. 



The veins of the lower extremity are the deep and superficial. The 

 deep veins accompany the branches of the arteries in pairs, and form 

 the venae comites of the anterior and posterior tibial and peroneal 

 arteries. These veins unite in the popliteal region to form a single 

 vein of large size, the popliteal, which successively becomes in its 

 course the femoral and the external iliac vein. 



