DR. J. MURIE ON THE ANATOMY OF THE SBA-LION. 541 
The ulnar artery.—From the main artery below the elbow-joint a short flange pro- 
ceeds ulnarwise, and at a quarter of an inch distance splits into three. One slants across 
the ulnar head of the flexor sublimis and goes down the arm as the ulnar artery to the 
wrist, there splitting into three small digital vessels. These three vessels are distributed 
to the fifth and fourth digits. The outer one, given off highest, runs along the ulnar 
side of the fifth digit ; the next goes a short way single and then divaricates, one branchlet 
supplying the radial side of the fifth digit, the other the ulnar side of the fourth digit. 
From the short trunk above spoken of the anterior ulnar recurrent diverges upwards 
toward the joint. The posterior ulnar recurrent is derived immediately below the 
above, and at an angle from the ulnar. It enters the substance of the flexor carpl 
ulnaris and the palmaris longus muscle. 
Radial artery —This, the chief continuation of the brachial into the forearm, passes 
downwards over the biceps and brachialis anticus muscles in front of the inner condyle, 
and afterwards beneath the pronator radii teres and the flexor carpi radialis. In the 
forearm it is situated nearly in the middle of the broad radius, superficial to and partly 
on the ulnar side of the radial head of the conjoined flexor profundus and pollicis. ‘Che 
tendon of the palmaris longus secundus obliquely crosses the artery above the wrist- 
joimt. Dipping beneath the superficial palmar fasciz, it then, at the proximal end of the 
metacarpals, splits into three divisions which form the main portion of the palmar arch. 
The largest pollicial branch crosses the radial side of the second metacarpal and sub- 
divides into two twigs which proceed respectively to the ulnar side of the pollex and 
radial side of the second digit. The second middle branch similarly subdivides into a 
couple of twigs, which run along the ulnar side of the second and radial side of the third 
digit. The third branch comes off the highest of the three, and, subdividing at the 
proximal end of the proximal phalanx, bifurcates, one twig going to the ulnar side of 
the third, and the other to the radial side of the fourth digit. This palmar arch is 
superficial to the nerves. 
Below the elbow and in the upper part of the forearm the radial sends off a recurrent 
branch, chiefly distributed to the muscles on the humerus and radial side of the joint. 
Other muscular branches are distributed in the forearm. 
Interosseous vessels.—Immediately below the derivation of the ulnar the common 
interosseous artery strikes off and is about half an inch long, it then splits into two 
branches. One of these, the posterior interosseous artery, dips between the radial 
and ulnar heads of the deep flexors above the oblique ligament. It is distributed to 
the pronator teres, extensor ossis metacarpi pollicis, &c. The second branch forms 
the anterior interosseous artery, from which, an inch below the commencement 
of the posterior interosseous artery, a muscular offshoot of moderate size diverges 
radially and goes to the long muscles of the radial side. A small branch, repre- 
senting the recurrent, goes upwards to the elbow-joint beneath the external lateral 
ligament. 
VOL VIII.—ParT Ix. June, 1874. 4 
