THE XFJK 



llOli 



right, and doos not rise so high into the iwck. The sulxhivian vein hcs ut a luwcr 

 level and under lover of the elaviele. Into tiie ahove curve rise the jileura and lung. 



The suprascapular and transverse cervical vessels run outwards, jiarallel 

 with the clavicle. The former lies behind the bone and sidx lavius; the hitter alsn 

 runs transversely outwards, across the root of the neck, but on a slightly higher 

 plane, and thus a little above the clavicle. 



Crossing the sterno-mastoid a little obli(juely, in a line drawn from the angle 

 of the jaw to the centre of the elaviele, runs the external jugular vein. About 

 an inch and a half aliove the clavicle it perforates the deej) cervical fascia, its coats 

 l)eing blended with the opening. The dilated ])art between this pf)int and the 

 subclavian vein is called the sinus, and is marked by two valves, neither of which 

 is usually perfect. Just above the clavicle the })()sterior and sui)rascai)ular, trans- 

 verse cervical, and a branch from the eei)halic veins, form a plexus over the third 

 part of the subclavian. 



Opening into the external jugular, in the middle or lower third of its course, is 



Fig. 676. — Keoiux ok the TiiiRr* P.vkt ok thic Sibci..\.vian Artery. 

 (The shoulder represented depressed.) 



(Bellamy.] 



Spleuius 



Levator anguU scapulae 



Scalenus posticus 



A SrPKRF/CIA L DE- 

 SCEXD/XO BRAXCH 

 OF THE CERVICAL 

 PLEXUS 

 BRA CI/Ll L PLEXUS 

 Tiansvcr.salis colli artery 

 (life),) 

 First serration of serratus 

 magnus 



PIIREXIC XERVE 

 Scalenus amicus 



.. oorration of serratus magnus 

 ^ lit /lit km it;iii 

 Sii/iriiscapulai artery 

 Snhclavian artery 



Suprascnptilar rein 

 Coito-coracoid membrane and rr/i/inlic rein 



the posterior external jugular, a vessel which l»egins in the occipital region 

 superficially and runs down in front of the anterior Itorder of the tra}>ezius, acro.ss 

 the ))osterior triangle. 



The spinal accessory enters the anterior Itorder of the sterno-mastoi<l from 

 one to one and a half inches l)elow the a]>ex of tlie mastoitl. along a line drawn 

 downwards and outwards from the angle of the jaw. Having traversed the muscle 

 obliciuely, it pursues a similar course acro.ss the posteri(»r triangle, disaitjtears on a 

 level with the sixth or seventh cervical spine beneath the trapezius, and descends 

 under this mu.«;cle internal to the vertebral border of the scapula ((^odlee). Just 

 above the centre of the sterno-mastoid, the small occipital, great auricular, and 

 transverse cervical nerves emerge, the first passing upwards and backwards to 

 the scalp, the second Upwards and forwards across the upper jxirt of the sterno- 

 mastoid to the ear. and the last turning straight forwards to the front of the neck. 



The phrenic nerve, taking its largest root fntm the fourtli cervical, would 

 begin deeply about the level of the hyoid l)one; thence descending under the sterno- 



