Electro-physiology and electro-therapeutics : showing the best methods for the medical uses of electricity / By Alfred C. Garratt.

reach the surface close along- the spine, and are reflected out- ward, to be distributed and lost in the integuments of the spinal region. The larger anterior branches of these first five converge into the brachial plexus. From this plexus there go out together six terminal branches. These may be considered in two divis- ions ; first, the humeral branches, or those that are found on the upper arm and shoulder; second, the descending branches, or those that supply the forearm and hand. Now, nearly all these nerves are in the first instance motors, i. e., first traversing and supplying the muscles; but they terminate by very many cuta- neous branches of great importance. The first we notice are the superior muscular nerves, that go to the sub-clavius, the rhom- boid, and the levator anguli scapula muscles. The next are the short thoracic nerves, (anterior,) which are two in number, and supply the pectoralis major, entering it, however, on its cos- tal surface, and send twigs to the deltoid, as also to the deeper parts of the pectoralis minor. Next, we notice the long thoracic nerve, also called the posterior thoracic, or the external respira- tory of Bell, passing down behind the plexus, but upon the broad serratus magnus muscle to its lowest serrations, where and in which it is lost, after supplying the whole muscle. Then we observe the supra-scapular nerve, descending from above the clavicle obliquely outward and downward to the supra-scapular notch; it then passes through the notch, crosses the supraspi- nous fossa, beneath only the supra-spinatus muscle, (mark this!) and then passing in front of the concave margin of the spine of the scapula, it enters the infra-spinous fossa, and is distributed to the muscles supra-spinatus and infraspinatus. Next are the subscapular nerves, two in number, distributed also to the mus- cle subscapularis. And, finally, still lower down on the shoul- der, we find the "inferior muscular nerves;" they are only three branches, distributed to the latissimus dorsi, and the teres major. So much for the shoulder. On the upper arm we notice the great " external cutaneous " nerve, which arises first in common with the median nerve from the cervical plexus, pierces the coraco-brachialis muscle, and