THE PERIPHERAL NERVOUS SYSTEM. 387 
or both of the anterior thoracic nerves (# and x), of the pos- 
terior thoracic (#), the three subscapular nerves (c, e, and 2), 
the axillary (d), musculocutaneus (/), radial (%), and median 
(g) nerves. The eighth cervical (V///) supplies parts of one 
Fic. 159.—DIAGRAM OF THE RIGHT BRACHIAL PLEXUS. 
V, VI, Vil, V7, the fifth to eighth cervical nerves. 1, the first thoracic 
nerve. «, phrenic nerve; J, suprascapular; 4’, nerve to serratus anterior and levator 
scapulze muscles; ¢, first or cranial subscapular nerve; ¢, axillary nerve; e, second 
subscapular; 7, musculocutaneous; g, median; 4, radial; z, third subscapular; 7, ulnar; 
2, second anterior thoracic; 7, medial cutaneous; , posterior thoracic; , first 
anterior thoracic. 
of the anterior thoracic nerves (&), the caudal one of the sub- 
scapular nerves (¢), the radial (4), median (g), and ulnar (7) 
nerves. The first thoracic (1) curves craniad, so as to leave 
the thorax on the cranial side of the first rib; it supplies the 
median cutaneous nerve (/) and parts of the radial (%), ulnar 
(/), and median (g) nerves; sometimes also a part of one (£) 
of the anterior thoracic nerves. 
The following are the nerves which arise from the brachial 
plexus: 
A. Nerves of the Shoulder and Breast (Fig. 160). 
1. Nn. thoracici anteriores. — There are: two anterior 
thoracic nerves. One (Fig. 160, 4, Fig. 159, 7) arises from the 
seventh cervical and passes to the pectoral muscles (9) along 
with the anterior thoracic artery. The other (Fig. 159, &; Fig. 
160, g and7) arises usually by two roots, one from the eighth cer- 
vical, one from the first thoracic; it passes along with the long 
thoracic artery to be distributed to the pectoralis muscles (Fig. 
160, 8) and sometimes also to the latissimus dorsi (7). 
