216 Anatomy of the Rabbit. 



point — a short distance in front of the elbow — into the radial and 

 ulnar arteries. Its chief branches on the arm are the ulnar 

 collateral arteries (superior, middle, and inferior) to the muscles 

 and the elbow joint. 



The radial artery (a. radialis) passes distad on the ventro- 

 medial border of the radius, in company with the median nerve, 

 lying at first between the flexor carpi radialis and the radial portion 

 of the flexor digitorum profundus. Toward the distal end. of the 

 radius it crosses the ventral surface of the tendon of the flexor carpi 

 radialis, and appears in a superficial position on the medial border 

 of the carpus. It reaches the volar surface of the hand after passing 

 obliquely across the tendon of the flexor digitorum sublimis. 



The ulnar artery (a. ulnaris) crosses the ulna obliquely from its 

 origin, reaching in this way the lateral border of the flexor carpi 

 ulnaris, along which it passes to the end of the forearm and. to the 

 ulnar side of the pisiform bone. It passes to the ventral surface 

 of the fifth digit, and then turns across the hand, forming the volar 

 arch. 



**The single brachial vein (v. brachialis) accompanies the brachial 

 artery and lies behind it. It is formed in front of the elbow by the 

 union of two vessels, the radial and ulnar veins, which accompany 

 the corresponding arteries and join one another at the point of 

 separation of the latter. The radial vein anastomoses with the 

 radial portion of the cephalic at a point distal to the middle of the 

 forearm. 



The cephalic vein (v. cephalica) is a large superficial vessel 

 appearing on the dorsal surface of the forearm. From the radial 

 side of the latter it receives a large tributary which anastomoses 

 with the radial vein. It is accompanied by branches of the super- 

 ficial ramus of the radial nerve. It passes to the front of the arm 

 across the angle of the elbow, lying at first on the anterior margin 

 of the lateral head of the brachialis, and afterwards on the lateral 

 surface of the arm between the abductor brachii superior and the 

 anconaeus lateralis. It disappears from this surface in the trian- 

 gular space enclosed by these muscles and the insertion of the 

 levator scapulae major, receiving at this point a large tributary from 

 the shoulder. It appears on the medial surface of the shoulder at 



