22 THE SURGICAL ANATOMY OF THE HORSE 



fetlock (64), and it then disappears, to be ultimately inserted into the 

 semilunar crest on the inferior aspect of the pedal bone. 



This muscle is a flexor of the knee, fetlock, pastern, and corono- 

 pedal joints, and is supplied by the ulnar and median nerves. 



The Arteries 



The Axillary Artery (17). — The severed end of this vessel is 

 represented where it lies in the loop formed by the roots of the 

 median nerve (17). 



It crosses the tendon of the subscapularis muscle and passes on to that 

 of the teres major, where it becomes directly continued as the brachial 

 artery. 



The Suprascapular Artery (9). — This is a branch of the axillary artery, 

 It runs for a short course in a retrograde manner from the parent vessel 

 and splits up into a number of branches. One of these passes across the 

 subscapularis and dips in between this muscle and the supraspinatus. 

 Another passes from it to the anterior deep pectoral muscle. These two 

 branches are represented distinctly in the plate. 



The Subscapular Artery (10). — This is a large vessel, which is also a 

 branch of the axillary. It leaves the axillary where the latter passes 

 across the line of apposition of the subscapularis and teres major muscles. 

 The artery quickly disappears between these two muscles and its main 

 continuation passes upwards along the glenoid border of the scapula. 

 (In the plate the artery is shown throughout its course, owing to these 

 muscles having been separated from one another.) 



The Artery to the Latissimus Dor si (18). — This is a vessel of 

 considerable calibre, which may either come off as a branch of the 

 axillary artery or as a branch of the subscapular artery. It takes a course 

 backwards across the teres major muscle to supply the latissimus dorsi. 



The Brachial Artery (20). — It has been already stated that this artery 

 is the direct continuation of the axillary. It takes a vertical course 



