THE UPPER LIMB 397 



and, it iflay be. the anticubital glands; but the latter are inconstant. There 

 are no 'uperficial h-mphatic glands in the hand or forearm. 



The deep glands principedly represent the axillary and infra-clavicular 

 glands. A few deep lymphatic glands, however, of very small size are some- 

 times met with in connection with the deep lymphatic vessels which accom- 

 pany the arteries of the forearm and the brachial artery. One or two deep 

 lymphatic glands are also sometimes met with in the groove between the 

 deltoid and pectoralis major muscles, along the cephalic vein. 



Ssperficial Glands. Deep Glands. 



1. Internal epicondylar. i. Axillary. 



2. Anticubital (inconstant). 2. Infra-clavicnlar. 



3. Radial (inconstant). 



4. Ulnar (inconstant). 



5. Anterior interosseous (inconstant). 



6. Brachial (inconstant). 



7. Cephalic (inconstant). 



Development of Arteries of Upper Limbs. 



The arterial stem of the left upper hmb is developed entirely from the 

 seventh left cervical segmental artery, in association with the left vertebral 

 artery. The component arteries of this stem, from above downwards, are as 

 follows: (i) The subclavian artery; (2) the axillary artery; (3) the brachicil 

 artery; and (4) The anterior interosseous artery. The arterial stem of the 

 right upper hmb is developed from the fourth right arterial arch, a portion of 

 the right dorsal aorta, and the seventh right cervical segmental artery, in 

 association with the right vertebral arter\'. The component arteries of this 

 stem are as on the left side. 



Before the adult condition of the arteries is reached, several stages of 

 development have to be passed through. 



(i) As the anterior interosseous artery becomes diminished, another artery 

 springs from the brachial a short distance below the elbow-joint. This new 

 vessel accompanies the median nerve, and is called the median artery. 



(2) The medizin artery superiorly furnishes a branch, which becomes the 

 ulnar artery. 



(3) As the median artery becomes diminished, a vessel springs from the 

 brachial artery about the centre of the brachial region. This vessel is called 

 the primary radial artery, and it accompanies the radial nerve. 



(4) As the upper part of the primary radial artery atrophies, the brachial 

 artery gives off another branch just below the elbow -joint, which soon joins 

 the primjiry radicd, and so the permanent radial artery is formed. 



Development of Veins of Upper Limbs. 



The veins of each upper hmb form two groups — superficial and deep. 

 The superficial veins are developed prior to the deep, the latter accompanying 

 the arteries. 



The primitive vein is the primary ulnar or postaxlal vein, which receives 

 distaUy the digital veins, and opens proximally into the anterior cardinal vein. 

 At a later period the cephalic vein is formed as an outgrowth from the external 

 jugular vein, but it subsequently acquires its permanent connection with 

 the upper part of the axillary vein. 



The distal portion of the primary ulnar vein disappears. Its proximal 

 portion persists and gives rise to the basilic, axillary, and subclavian veins. 



From the distal end of the basilic vein the anterior and posterior ulnar 

 veins and the median basilic vein are developed. 



The radial and median cephalic veins grow distally from the cephalic vein. 



The median vein is developed from the median basihc and median cephalic 



