284 ANATOMY OF THE DOMESTIC FOWL 



first main root of the plexus, and passes outward through the fora- 

 men coracoideum of the sternal ligament. 



The sterno-coracoideus, a small nerve which extends downward 

 from the plexus. 



The somewhat large posterior coraco-brachialis, nerve which 

 springs from one or two middle roots of the plexus and accompanies 

 the pectoral nerve. 



The anterior thoracic, a large nerve which springs from two or 

 three of the posterior roots of the plexus and extends to the shoulder 

 cavity where it branches. The anterior branch is distributed to 

 the patagium and the front part of the pectoral muscles. The 

 posterior branch supplies muscles along the side of the thorax and 

 extends into the abdominal muscles. 



The anterior coraco-brachialis, a small nerve which springs mostly 

 from the inferior longus brachialis, passes to the distal end of the 

 tuberculum humeralis radii, then passes backward between the 

 front part -of the humerus and the biceps, where it supplies the 

 anterior coraco-brachialis. 



The cutaneous brachialis et inferior brachialis, a small nerve which 

 springs from the posterior roots of the plexus. It is distributed to 

 the skin of the region and branches are given off to the patagii and 

 the ventral wing surface. A few branches extend as far as the upper 

 arm. 



The brachialis longus inferior (Fig. 68, No. 2) , a continuation of 

 the main trunk of the inferior brachial nerve, which comes out of 

 all the plexus roots except the first. It gives off some branches to 

 the pectoral region and then enters the shoulder cavity. It gives 

 off the anterior coraco-brachialis, passes down the humerus in an 

 S-shape, and divides into two branches, the ulnar and the median. 



The ulnar nerve (Fig. 67, No. 3) divides into numerous branches 

 which are distributed to the ulnar side of the forearm and the hand. 

 The ulnar nerve passes below, the skin of the ulnar outside rim of the 

 forearm and gives branches to the carpi ulnaris, finally supplying 

 the flexor digitorum; it then passes with the tendon of this muscle 

 downward to the interosseous dorsalis, the abductor indicis, or 

 flexor minimi brevis, the flexor pollicis, and the abductor pollicis, 

 or extensor proprius pollicis. 



The median nerve (Fig. 67, No. 2) extends down the arm and gives 

 branches to the biceps muscle, and to the patagii region. Continu- 

 ing, the median nerve supplies the pronator muscle and the brachi- 



