CIRCULATORY APPARATUS. 87 



ferior articular surface of the humerus, where it terminates m the 

 anterior and posterior radial arteries. 



It is in relation to the median nerve on the outside and the 

 coraco-radialis.on the inside. 



Its branches are — 



7. Prehinneral ox anterior circumflex 0/ shoulder. 

 To shoulder joint and muscles of upper humeral region, anasto- 

 mosing with posterior circumflex. 



2 . External collateral of elbow. 



To muscles in vicinity of elbow joint, v/here it anastomoses 

 with anterior radial. 



3. hiternal collateral ox ulnar. 



To internal border of arm and forearm, to carpus, anastomos- 

 ing with posterior radial, and accompanying the ulnar nerve and 

 vein. It sends branches to muscles, to elbow joint and humerus. 



4. Coraco-radial. 

 To muscle. 



ANTERTOR RADIAL. 



The smaller of two branches of humeral, extends along front 

 of radius to front of carpus, where it splits up into smaller 

 branches, which supply the articulation, and anastomose with 

 posterior radial and interosseous. It gives off branches also to 

 elbow joint and muscles. 



POSTERIOR RADIAL. 



The larger of two subdivisions of humeral, passes to side on 

 internal ligament of elbow, along inner side of radius, to its in- 

 ferior portion, where it divides into the common interosseous, 

 metacarpal 2ind collateral artery of the cannon. 



The branches in its course are to elbow and muscles of forearm. 



INTEROSSEOUS OF FOREARM. 



Arises near radio-ulnar arch, and passes along groove between 

 ulnar and radius. Gives off branches to the elbow, anti-brachial 

 muscles, and terminates at the carpus by numerous anastomoses. 



