610 THE VEINS. 



branches and the subcutaneous thoracic vein, unites near the shoulder-joint 

 with the subscapular trunk, to form the axillary vein. 



We will study all these branches in the inverse order of their 

 enumeration. 



1. Subscapular Vein. 



A vary considerable vessel, whose disposition resembles that of the 

 subscapular artery, though presenting some special peculiarities whose 

 study does not deserve a moment's delay ; for example, it most frequently 

 receives the satellite vein of the prehumeral artery. 



2. Humeral Vein. 



Placed behind and within the humeral artery, this vessel commences 

 above the articulation of the elbow, being formed at this point by the anasto- 

 mosing system of veins from the fore-arm, and terminates below the shoulder- 

 joint in opening into the subscapular vein. 



Independently of the subcutaneous thoracic vein, which will be studied 

 in a special manner, the humeral vein receives on its way several collateral 

 satellites of the branches emanating from the humeral artery. One of these, 

 the epicondyloid, is only a continuation of the ulnar vein. 



Very often we find a second humeral vein in the deep region of the arm ; 

 this is an accessory vessel, parallel to the preceding, and situated ^opposite 

 it in front of the artery. 



3. Subcutaneous Thoracic or Spur Vein. 



This vein, which is important to know, as bleeding is sometimes 

 practised from it, commences on the flank and belly by numerous super- 

 ficial divisions, which unite in two principal roots, and afterwards become a 

 single trunk, placed in the substance, or on the external surface of the 

 panniculus carnosus, where it is directed forwards in following the superior 

 border of the large pectoral muscle, accompanied by an arterial ramuscule 

 and a thick nerve. It insinuates itself beneath the olecranian muscles, 

 and finally terminates in the humeral vein by opening into the branch that 

 follows the deep muscular artery. 



4. Deep Veins of the Fore-arm. 



A. ANTERIOR EADIAL VEIN. This follows the same track, and affects 

 the same variations, as the corresponding artery. 



B. POSTERIOR RADIAL VEINS. The posterior radial artery is always 

 accompanied, and, as it were, enveloped, by a fasciculus of three or four 

 venous branches, which frequently anastomose with each other, and are 

 reinforced by collateral branches, among which the interosseous vein must 

 be noted. 



These radial branches commence above the carpus, by continuing the 

 metacarpal veins. They concur to form the humeral vein, in joining the 

 other antibrachial veins at the inferior extremity of the arm. 



C. ULNAR VEIN. This vessel is lodged, with the nerve and small artery 

 of the same name, in the interstice of the oblique and internal flexors of the 



