286 THE VASCULAR SYSTEMS 



maxillary trunk. It descends obliquely across the sterno- 

 mastoid, lying between the platysma and fascia. Above the 

 clavicle it pierces the fascia and joins the subclavian at the outer 

 border of the scalenus anticus; sometimes it joins the internal 

 jugular. It receives the posterior external jugular, anterior 

 jugular, transverse cervical, and suprascapular veins. The two 

 latter correspond to the arteries of the same name. 



The posterior external jugular drains the occipital and pos- 

 terior cervical regions. 



The anterior jugular descends along the front of the neck 

 from the submaxillary region, pierces the fascia near the inner 

 end of the clavicle, and joins the external jugular, sometimes 

 the subclavian. This vein and its fellow are joined by a cross- 

 branch just above the sternum, and it receives tributaries of 

 communication from the submental, external jugular, and facial. 



The internal jugular vein commences at the jugular foramen 

 just below the junction of the inferior petrosal with the lateral 

 sinus, and descends with the external carotid, then with the 

 common carotid, to join at a right angle with the subclavian vein 

 behind the clavicle, thus forming the innominate vein. It is 

 placed external to the carotid vessels, lying in the same sheath 

 with each in turn. 



It receives the following tributaries: 



The common facial (vide antea) and the middle thyroid. 



The superior thyroid. 



The pharyngeal wins. 



The lingual veins, including the ratline, dorsal rein of the tonyiu', 

 and the rcnos com Hex of the lingual artery. 



The inferior petrosal sinus is regarded by some anatomists as 

 the first tributary. 



The cerebral veins. These are divided into two sets, the 

 superficial and the deep. 



Superficial Veins. The superior, ten to twelve on each side, 

 consist of the anterior, middle, and posterior veins which run 

 in the sulci, and, joining with branches from the mesial aspect 

 of the brain, empty into the superior longitudinal sinus. The 

 inferior consists of the middle cerebral vein, in the Sylvian 

 fissure, which joins the cavernous sinus, and the great anasto- 

 motic vein, in the posterior branch of the same fissure, communi- 

 cating with the middle meningeal veins and joining the superior 

 petrosal sinus. 



