132 ANTHROPOLOGY. 



nicates with the superior cervical ganglion of the sympathetic above, and 

 with the continued cord of this nerve lower down ; also with the pneumo- 

 gastric, lingual, and spinal accessory. Besides numerous muscular fila- 

 ments, it sends off various cutaneous branches, which are either ascending 

 or descending. 



The ascending branches are : a. Superficialis colli, arising about the 

 middle of the neck, and distributed on the anterior and lateral region of the 

 neck. h. The auricularis magnus arises in the same situation and ascends 

 nearly parallel and posterior to it ; at the parotid gland it divides into two 

 branches, one superficial, the other deep, which supply the external ear and 

 sides of the scalp, c. The occipitalis minor arises near the last from the 

 second cervical nerve, and ascending is distributed to the skin and occipito- 

 frontalis muscle. 



The descending branches are superficial and deep. The superficial 

 branches, or supra-clavicular, are long and rather large ; they arise from 

 the third and fourth cervical nerves, and pass to muscles of the neck and 

 shoulder. The deep descending branches are : a. The muscular. These 

 arise from different parts of the plexus, and are principally distributed to 

 the trapezius, levator anguli scapularis, and sterno-mastoid muscles, b. The 

 communicatiny branches are very numerous. From the second and third 

 roots of the plexus descends the communicaiu noni to the hyoid apparatus 

 c. The most important branch of the cervical plexus is the internal respi- 

 rator// or pjhrenic nerve. This arises from the lower part of the plexus, and 

 descending on the anterior scalenus muscle, enters the thorax between the 

 subclavian vein and artery ; passing down the middle mediastinum to the 

 diaphragm on the side of the pericardium, the left phrenic takes an oblique 

 course round the base of the heart. 



PI. 137, fig. 15, superficial nerves of the cervical plexus : \ superficial 

 temporal nerve of the fifth pair ; ', occipitalis magnus ; ', superior cutaneous 

 cervical nerve, from the facial ; % auricularis magnus ; ^, occipitalis minor ; 

 ", an inconstant occipital nerve, '' ', some posterior cutaneous branches ; 

 ", accessory nerve; ", supra-scapular nerve; '°, supra-clavicular nerve; 

 ", middle cutaneous cervical nerve ; ", a small branch accompanying the 

 jugular vein; ", connexion of the cervical plexus with the facial nerve. 



The anterior divisions of the last four cervical, and that of the first 

 dorsal, unite to form the brachial plexus. 



8. The Brachial Plexus. This plexus is broad and flat, the nerves 

 forming it being very large, particularly the inferior. It is situated at the 

 lower and lateral parts of the neck, between the scalenic muscles and the 

 subclavian artery ; it then passes under the clavicle into the axilla, where it 

 rests on the serratus magnus, ending opposite to the coracoid process. The 

 numerous branches of this plexus may be arranged into two orders, one 

 (supra-clavicular) arising above the clavicle, the other {axillary) arising 

 from below this bone. 



The suptra-clavicular branches are as follows ; 1. For the subclavian 

 muscle. 2. Small branches from the upper root of the plexus to the 

 scaleni, levator anguli, and rhomboidei muscles. 3. Posterior thoracic or 

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