64 THE SUPERIOR EXTREMITY 



superficial veins on the dorsum of the hand communicate through 

 the interdigital clefts with the deep and superficial veins of the 

 palm. 



The superficial veins on the volar aspects of the fingers and in the palm 

 are small, and cannot as a rule be displayed in an ordinary dissection, but, 

 springing from a network in the superficial fascia of the palm, or appearing 

 in the superficial fascia of the volar aspect of the wrist, there is occasionally 

 a median antebrachial vein which passes proximally, along the middle 

 of the volar aspect of the forearm, towards the elbow. A short distance 

 distal to the elbow it either joins the median cubital vein or it divides 

 into two branches, the median basilic and the median cephalic, which 

 terminate respectively in the basilic and cephalic veins. 



Accompanying the various superficial veins of the superior extremity 

 there are numerous lymph vessels which collect lymph from the regions 

 drained by the veins. Those which accompany the proximal part of the 

 cephalic vein, and which are derived partly from the dorsum of the 

 forearm and partly from the dorsum of the arm and the lateral part of 

 the shoulder, pass to the delto-pectoral and infraclavicular lymph glands ; 

 some of the lymph vessels which accompany the basilic vein end in the 

 superficial cubital glands, above the medial epicondyle ; the remainder, and 

 the efferents of the superficial cubital glands, accompany the proximal part 

 of the basilic vein, and, after piercing the deep fascia, they terminate either 

 in the brachial glands or the lateral group of axillary glands (Fig. 9). 



The superficial lymph glands can often be found by a careful dissector, 

 but the superficial lymph vessels are difficult to demonstrate in an ordinary 

 dissecting-room " part." They appear as fine white strands, and are most 

 easily distinguished as they enter or leave the glands. 



Vena Cephalica. The cephalic vein commences at the 

 radial end of the venous arch on the dorsum of the hand. 

 It receives the two dorsal digital veins from the thumb, and 

 then turns round the radial border of the distal part of the 

 forearm and ascends to the region of the elbow; there the 

 greater part of the blood which it carries is transmitted to the 

 basilic vein by the large median cubital vein. Proximal to 

 the level of the median cubital vein, the cephalic vein ascends 

 either along the lateral part of the biceps, or in the groove 

 at the lateral border of the biceps, to the lower border of the 

 pectoralis major; there it pierces the deep fascia (Fig. 31), and 

 then continues proximally in the groove between the pectoralis 

 major and the deltoid to the delto-pectoral triangle. In the 

 delto-pectoral triangle it crosses the lateral part of the pectoralis 

 minor, and turns medially between the clavicular part of the 

 pectoralis major and the costo-coracoid membrane. In this 

 terminal part of its course it lies anterior to the axillary artery, 

 but is separated from the artery by the costo-coracoid mem- 

 brane. Finally it pierces the costo-coracoid membrane and 

 joins the axillary vein. It receives (i) the dorsal digital veins 



