Spinal Nerves. 



147 



491. The Superficial Nerves of the Neck. 



7. N. superficialis s. subcutaneus colli turns around the M. sterno-deido- 

 mastoideus from behind forwards, and divides into two branches, an ascending, 

 N. subcutaneus colli medius, and a descending, N. subcutaneus colli inferior ; the 

 former accompanies the external jugular vein and communicates with the cer- 

 vico-facial division of the facial nerve. Both supply integument and platysma. 



8. Supraclavicular nerves, Nervi supraclaviculares, three or four 

 in number, descend to the clavicle and supply the skin of the anterior thoracic 

 and acromial regions. 



9. Phrenic nerve, N. phrenicus (internal respiratory nerve of Bell), 

 arises from the third and fourth cervical nerves, descends in front of the 

 M. scalenus anticus to the chest, and communicates with the brachial plexus and 

 the middle and inferior sympathetic ganglia. It enters the thorax between Vena 

 innominata and subclaviaii artery and passes between the pericardium and pleura 

 to the diaphragm, whose Pars costalis and Pars lumbalis it supplies. 



The posterior branches of the lower cervical nerves pass to the deep 

 muscles and skin of the neck. 



Heitzmann, Atlas. II. 20 



