966 



THE VASCULAE SYSTEM. 



The upper surface of the first rib is below the vein. 



Tributaries. Whilst the subclavian vein is the direct continuation of the axillary 

 vein, and receives, therefore, the blood from the upper extremity, it has, as a general 

 rule, only one named tributary, viz., the external jugular vein. 



Vena Jugularis Externa. The external jugular vein (Fig. 785) is formed on 

 the superficial surface of the sterno-mastoid muscle, a little below and posterior to 

 the angle of the mandible, by the union of the posterior auricular vein with a branch 

 from the posterior facial vein (O.T. temporo-maxillary). In many cases the branch 



Superficial temporal vein 



Occipital vein 

 Internal maxillary veins 



Posterior facial vein 

 Posterior auricular vein 



Posterior facial vein 



Posterior external 

 jugular vein 



Transverse cervical vein 



Supra-orbital vein 

 Angular vein 



Lateral nasal vein 



Superior labial vein 



Inferior labial vein 

 Anterior facial vein 



Secondary inferior 

 labial vein 



Anastomosis between 

 common facial and 

 anterior jugular veins 

 Anterior jugular vein 



External jugular vein 



FIG. 785. SUPERFICIAL VEINS OF THE HEAD AND NECK. 



from the posterior facial vein is so preponderantly large that it is more correct to 

 describe the external jugular vein as commencing as a branch of the posterior facial 

 vein. After its formation the external jugular vein descends, with a slight obli- 

 quity backwards, to the anterior part of the subclavian portion of the posterior 

 triangle of the neck, where it pierces the deep fascia, crosses in front of the third 

 part of the subclavian artery, and terminates in the subclavian vein. 



Whilst on the surface of the sterno-mastoid muscle it is covered by the super- 

 ficial fascia, and platysma muscle, and it lies parallel with the great auricular 

 nerve ; after crossing the nervus cutaneus colli (O.T. trans, cervical) it reaches the 

 posterior border of the sterno-mastoid, where it receives a tributary called the 

 posterior external jugular vein, which commences in the superficial tissues of 

 the upper and back part of the neck, and runs downwards and forwards, across the 



