AXILLARY, AND ITS BRANCHES. 211 



illary plexus of nerves. In front it is separated from the sub- 

 clavian vein by the insertion of the scalenus anticus. It is 

 placed at the bottom of the depression between the sterno-mas- 

 toideus and the trapezius, being covered by the skin, the pfa- 

 tysma myodes, and some loose cellular substance below the 

 latter. It then descends between the first rib and the subcla- 

 vius; escaping from below the latter, it is covered in front by 

 the outer margin of the pectoralis major until it reaches the 

 lower part of the axilla; and in this course it has the following 

 relation to other parts : it passes then under the insertion of the 

 pectoralis minor, under the shoulder joint, then along the in- 

 ternal face of the coraco-brachialis muscle ; it has the axillary 

 vein in front of it, and the axillary nerves plaited around it as 

 far down as the coracoid process, when they begin to disperse. 

 This artery in emerging from the axilla is placed upon the an- 

 terior face of the insertion of the latissimus dorsi: it then runs 

 out the length of the coraco-brachialis, and is afterwards con- 

 ducted along the inner margin of the biceps flexor cubiti and 

 its tendinous termination; it lies upon the anterior face of the 

 brachialis internus; and goes beneath the aponeifrosis coming 

 from the tendon of the biceps at the bend of the arm. In the 

 arm it is concealed only by the integuments and fascia, and 

 is bordered internally by the brachial .vein and the median 

 nerve. 



This great trunk of the upper extremity loses the name of 

 subclavian, to be called Axillary Artery, (Art. Axillaris,) from 

 the subclavian muscle to the lower margin of the arm-pit: and 

 from the latter place to the elbow joint, it is named Brachial 

 Artery, (Art. Brachialis.} It sends off many interesting 

 branches to the thorax, to the shoulder, and to the arm; and, 

 finally, terminates a little below or at the elbow joint by bifur- 

 cating. 



Of the Branches of the Axillary Artery. 



1. The Superior Scapular Artery (Art. Dorsalis Superior 

 Scapula) varies considerably in its origin. Sometimes it is a 

 branch of the subclavian, sometimes of the inferior thyroid, and 

 it frequently comes from the upper part of the axillary ; so that 



