504 NEUROLOGY. 



cesses, and form the deep cervical plexus^ from which the deep 

 muscles are supplied. 



Inferior Branches. — The inferior divisions of the cervical 

 nerves gradually increase in size from the first to the last. They 

 separate into two distinct groups, composed of the anterior six, 

 which furnish branches to the muscles and skin of the breast, 

 and of the lateral and anterior part of the neck, transmitting 

 intercommunicating branches, which form a vast network known 

 as the superficial cervical plexus, and which is traversed by 

 the cervical branch of the facial and an important branch from 

 the spinal accessory nerves. The last two, together with a branch 

 from the sixth, join the two first dorsal nerves to form the 

 brachial plexus. 



The inferior branches of the first cervical nerve pass through 

 the foramen in front of the atlas in company with the occipital 

 artery and vein, cross the rectus capitis anticus major muscle, 

 and the spinal accessory nerve, and, describing a curve towards 

 the top of the trachea, enter the subscapulo-hyoideus muscle, 

 where they terminate in numerous branches. In their course 

 they furnish filaments to the three recti muscles, to the thyro- 

 hyoid, sterno-thyro-hyoideus, sterno-maxillaris, and the muscles 

 connecting the hyoid bone to the larynx, and communicate with 

 the superior cervical ganglion, the spinal accessory, and hypo- 

 glossal nerves. 



The inferior branch of the second cervical nerve descends under 

 the posterior oblique, and is distributed by numerous branches to 

 the rectus capitis anticus * major and minor, levator humeri, 

 deprimens aurem, retrahentes aurem, and subscapulo-hyoideus 

 muscles ; to the outer side of the concha, and to the panniculus^ 

 and skin, communicating with a branch of the spinal accessory 

 and cervical branch of the facial nerves, and with the inferior 

 cervical ganglion of the sympathetic. 



The inferior branches of the third, fourth, fifth, and sixth 

 cervical nerves pass through the intertransverse muscle, and divide 

 into deep and superficial branches, the one being distributed to 

 the deep muscles of the neck and anterior part of the shoulder, 

 and the other to the skin of the neck and the panniculus. The 

 deep branches of the sixth and seventh, and a filament from the 

 fifth help to form the phrenic or diaphragmatic nerve. 



The seventh cervical nerve, a very large nerve, passes between 

 the two portions of the scalenus muscle, and helps to form the^ 



