412 JAMES CRAWFORD WATT 



with the radial nerve through the musculospiral groove, and the 

 superior and the inferior ulnar collaterals, running medially 

 alongside the ulnar nerve. 



At the elbow the brachial artery (fig. 8) took the astonishing 

 course of passing behind both the biceps tendons and lying on 

 the surface of the brachialis muscle. Just beyond this point the 

 arter}^ bifurcated into two branches which passed down the arm, 

 one on each side of the flexor digitorum sublimis. The lateral 

 branch, the radial artery, lay under the flexor carpi radialis 

 muscle, while the medial, the ulnar artery lay under the flexor 

 carpi ulnaris. Both arteries became lost in the dissection before 

 the wrist and hand were reached. 



VEINS 



Superficial veins (figs. 7 and 9) 



The cephalic vein (C. F.) is present here, starting in the hand 

 and running on the lateral (apparently dorsal) border of the 

 dorsal surface of the forearm, across the skin web at the elbow, ' 

 up the lateral side of the arm, dividing into two channels. These 

 turn ventrally below the insertion of the deltoid, reuniting here, 

 then pass between the deltoid and pectoralis major muscles to 

 terminate deeply in the thoracoacromial vein. 



The basilic vein (B. V.) starts also at the wrist, and runs up 

 on the medial border of the dorsal surface, turning medially to 

 the ventral surface just above the medial epicondyle of the 

 humerus. Here it passes under the deep fascia of the arm, run- 

 ning in the groove medial to the biceps as far up as the axilla 

 where it unites with the common trunk formed by the union of 

 the brachial venae comites to form the axillarj^ vein. 



Across the back of the elbow a large vein connects the basilic 

 and cephalic veins transversely. 



The median vein (M. V.) courses up the middle of the ventral 

 surface of the forearm as far as the bend of the elbow where it 

 divides into two large branches, the median basilic and median 

 cephalic. 



