664 



ANGIOLOGY 



and the medial anterior thoracic nerves. It is provided with a pair of valves oppo- 

 site the lower border of the Subscapularis ; valves are also found at the ends of the 

 cephalic and subscapular veins. 



The subclavian vein (v. subclavia), the continuation of the axillary, extends 

 from the outer border of the first rib to the sternal end of the clavicle, where it 

 unites with the internal jugular to form the innominate vein. It is in relation, in 

 front, with the clavicle and Subclavius; behind and above, with the subclavian 

 artery, from which it is separated medially by the Scalenus anterior and the phrenic 

 nerve. Below, it rests in a depression on the first rib and upon the pleura. It is 

 usually provided with a pair of valves, which are situated about 2.5 cm. from its 

 termination. 



AXILLARY 



ARTERY 



MUSCULO- 



CUTANCUS NERVE 



MEDIAN NERVE 



ANTERIOR 

 CIRCUMFLEX 



LONG THORACIC 



Fid. 576. The veins of the right axilla, viewed from in front. (Spalteholz.) 



The subclavian vein occasionally rises in the neck to a level w r ith the third part 

 of the subclavian artery, and occasionally passes with this vessel behind the Scalenus 

 anterior. 



Tributaries. This vein receives the external jugular vein, sometimes the anterior 

 jugular vein, and occasionally a small branch, which ascends in front of the clavicle, 

 from the cephalic. At its angle of junction with the internal jugular, the left 

 subclavian vein receives the thoracic duct, and the right subclavian vein the right 

 lymphatic duct. 



The Veins of the Thorax (Fig. 577) 



The innominate veins (vv. anonymas; brachiocephalic veins) are two large trunks, 

 placed one on either side of the root of the neck, and formed by the union of the 

 internal jugular and subclavian veins of the corresponding side; they are devoid 

 of valves. 



The Right Innominate Vein (v. anonyma dextra) is a short vessel, about 2.5 cm. 

 in length, which begins behind the sternal end of the clavicle, and, passing almost 

 vertically downward, joins with the left innominate vein just below the cartilage 



