AXILLARY ARTERY 



191 



subclavian vein is in front of it. The right subclavian is a branch 

 of the anonyma. Both subclavians end at the lower border of the 

 first rib. 



Branches. The vertebral branch runs upward through trans- 

 verse processes of the vertebrae to the brain. 



The internal mammary branch runs downward inside the chest 

 behind the costal cartilages in to the abdominal wall. It distributes 

 branches to the mammary gland and to intercostal muscles. 



FIG. 129. SUBCLAVIAN AND AXILLARY ARTERiES.-*-(r//.) 



The thyroid axis is a short trunk; it gives a branch to the thy- 

 roid gland and others to the neck and shoulder. 



An axis (artery) is a short vessel dividing at once into two or three. 



The axillary artery (Fig. 129) is a continuation of the sub- 

 clavian. It begins, therefore, where the subclavian ends in the 

 apex of the axilla, at the lower border of the first rib and con- 

 tinues through the axillary space. 1 



1 Axillary space, p. 368. 



