THE BRACHIAL AND AXILLARY VKTXS. 



539 



DEEP VEINS OF THE UPPER LIMB. 



The brachial artery and its various branches in the arm, forearm and hand, are 

 each accompanied by two veins, named vence comites. These companion veins lie 

 one on each side of the corresponding artery, and are connected with each other at 

 intervals by short cross branches, which in some places closely surround the artery. 

 Their distribution so nearly corresponds with that of the arteries, that they need not 

 be more particularly described. 



The "brachial veins, or vense comites of the brachial artery, terminate near the 

 lower margin of the subscapularis muscle by joining the axillary vein ; "hot unfre- 

 quently, however, the inner one unites with the basilic vein soon after that vessel 

 passes beneath the fascia. 



Between the several veins of the upper limb numerous communications exist in 

 their whole course. Thus, those which lie beneath the integument are freely 



Fig. 410. THE BLOOD-VESSELS OF THE AXILLA AND ARM PHOM THE INNER SIDE. (R. Quain.) 



The detailed description of this figure will be found at p. 436. The following numbers indicate 

 the principal veins : 2, 2, axillary vein ; 3, 3, basilic vein ; 3', median-basilic ; 4, 4', cephalic vein ; 6, 

 alar thoracic and subscapular ; 7, one of the brachial veins. 



connected to each other by cross branches in the hand and forearm. Not only are 

 the veins in each pair of venae comites united by short transverse vessels crossing 

 the artery which they accompany, but also those accompanying different arteries 

 have frequent connections with each other. Lastly, the subcutaneous and the deep 

 veins communicate freely, especially in the neighbourhood of the joints. This 

 general anastomosis ensures the continuance of the circulation during muscular 

 action in the frequent and varied motions of the limb. 



The axillary vein is of large size and collects all the blood returning from the 

 upper limb. It is formed by the continuation upwards of the basilic vein of the 

 arm, and extends, like the corresponding artery, from the lower border of the teres 

 major muscle to the outer margin of the first rib. It is placed on the inner side of 

 the axillary artery and has similar relations to the surrounding muscles. 



Lateral tributaries. The axillary vein receives in its course the several veins 

 corresponding to the branches of the axillary artery, viz., the two circumflex, sub- 



