458 POSTERIOR CERVICAL NERVES. 



branch of the facial and with the occipitalis minor. Previously to its 

 division the auricularis magnus nerve sends off several facial branches 

 which are distributed to the cheek. 



The Occipitalis minor arises from the second cervical nerve ; it curves 

 around the posterior border of the sterno-mastoid above the preceding 

 and ascends upon that muscle, parallel with its posterior border, to the 

 lateral and posterior side of the head. It is distributed to the integu- 

 ment and to the muscles of this region, namely, to the occipito-fronta- 

 lis, attollens and attrahens aurein, and communicates with the occipi- 

 talis major, auricularis magnus and posterior auricular branch of the 

 facial. 



The Acromiales and Claviculares are two or three large nerves which 

 proceed from the fourth cervical nerve and divide into numerous 

 branches which pass downwards over the clavicle, and are distributed 

 to the integument of the upper and anterior part of the chest from the 

 sternum to the shoulder. 



The Communicating branches are filaments which arise from the loop 

 between the first and second cervical nerve, and pass inwards to com- 

 municate with the sympathetic, the pneumogastric, and the hypoglossal 

 nerve. The three first cervical nerves send branches to the first 

 cervical ganglion ; the fourth sends a branch to the trunk of the sym- 

 pathetic, or to the middle cervical ganglion. From the second cervical 

 nerve a large branch is given off which goes to join the spinal acces- 

 sory nerve. 



The Muscular branches proceed from the third and fourth cervical 

 nerves ; they are distributed to the trapezius, levator anguli scapulae, 

 and rhomboidei muscles. 



The Communicans noni is a long slender branch formed by filaments 

 from the first, second, and third cervical nerves : it descends upon the 

 outer side of the internal jugular vein, and forms a loop with the de- 

 scendens noni over the sheath of the carotid vessels. 



The Phrenic nerve (internal respiratory of Bell) is formed by fila- 

 ments from the third, fourth, and fifth cervical nerves, receiving also a 

 branch from the sympathetic. It descends to the root of the neck, 

 resting upon the scalenus anticus muscle, then crosses the first portion 

 of the subclavian artery, and enters the chest between it and the 

 subclavian vein. Within the chest it passes through the middle 

 mediastinum, between the pleura and pericardium, and in front of the 

 root of the lung to the diaphragm to which it is distributed, some of 

 its filaments reaching the abdomen through the openings for the oeso- 

 phagus and vena cava, and communicating with the phrenic and solar 

 plexus, and on the right side with the hepatic plexus. The left 

 phrenic nerve is rather longer than the right, from the inclination of 

 the heart to the left side. 



POSTERIOR CERVICAL NERVES. The posterior division of the first 

 cervical nerve (sub -occipital), larger than the anterior, escapes from 

 the vertebral canal through the opening for the vertebral artery, lying 



