ANGEIOLOGY. 89 
anastomotica; 2, tne posterior ulnar recurrent, which ascends behind the 
inner condyle, and anastomoses with the anastomotica and inferior pro- 
funda; 3, the enterosseal artery, which passes backwards and divides into an 
anterior and a posterior branch, the former going to the carpal bones and to 
the sheaths of the extensor tendons, the latter to the extensor muscles; 4, 
muscular branches to the two layers of flexor muscles and to the skin; 
5, dorsalis carpi ulnaris, to the back part of the wrist and hand; 6, superficial 
palmar, which forms the palmar arch, bending across the palm of the hand 
to inosculate with branches of the radial artery; 7, palmaris profundus, 
which joins the deep palmar branch of the radial artery, thus completing 
the deep palmar arch. 
4, THE RADIAL ARTERY continues in the direction of the brachial artery, 
passing along the radial side of the forearm to the wrist; it then turns round 
the external lateral ligament of this joint, and passes forwards into the palm 
of the hand, terminating in three branches. It is accompanied by two 
veins, and the radial nerve is at its external side in the middle of the fore- 
arm. It passes over the biceps supinator brevis, pronator teres, flexor 
digitorum sublimis, flexor pollicis, and pronator quadratus. 
It gives off: 1, the radial recurrent to the supinators and extensors, 1nos- 
culating with the superior profunda; 2, muscular branches, to the flexors 
and supinators; 3, superficialis vole, to the small muscles of the thumb, 
inosculating with the ulnar artery, forming the superficial palmar arch; 4, 
dorsalis carpi radialis ; 5, dorsalis pollicis ; 6, radialis indicis ; 7, magna pol- 
licis, along the first metacarpal bone, and dividing into two branches; 8, 
palmaris profunda, which, passing across the metacarpal bones, joins the 
deep branch of the ulnar, and thus forms the deep palmar arch, from which 
branches proceed to the interosseal muscles, and to the bones and ligaments 
of the metacarpus, 
Pi. 184, fig. 2, arteries of the forearm and of the palm of the hand: 
', ulnar artery; *, anterior interosseal; *, posterior interosseal; *, superficial 
palmar; *, metacarpal branch; %’, digital branches; *, radial artery; °, its 
palmar branch; ", deep palmar arch; ", branch to the back of the hand; 
*,an anterior branch. ig. 6, arteries of the lower part of the forearm 
and the back of the hand: ’, branches of the external interosseal; *, dorsal 
branch of the radial; *, anastomoses on the back of the hand; *, artery of 
the thumb; ‘, third metacarpal branch. 
D. Thoracic Aorta. 
The thoracic aorta descends obliquely forwards from the termination of 
the arch to the diaphragm. It is inclosed in the posterior mediastinum ; the 
root of the left lung above, the heart and pericardium in the middle, and 
the cesophagus with the vagal nerves below, are anterior to it. The verte- 
bral column is behind. It gives off the bronchial, cesophageal, and inter- 
costal arteries. 
The bronchial arteries are two or three in number. They arise from the 
- forepart of the aorta, below the arch. They pass to either side, enter the 
back part of the root of each lung, and are lost in the cellular tissue of these 
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