660 



THE BLOOD-VASCULAR SYSTEM 



vein; opposite the angle of the jaw, veins from the pharyngeal plexus, and often a 

 communicating branch from the external jugular vein; opposite the bifurcation of 

 the carotid it is joined by the common facial, and a little lower down by the 

 lingual, sternomastoid, and the superior thyreoid veins. At the level of the cricoid 

 cartilage by the middle thyreoid when this vein is present. 



The inferior petrosal sinus is described with the other sinuses of the brain (p. 

 652) ; the pharyngeal plexus with the veins of the pharynx (see p. 659) ; and the 

 common facial vein with the superficial veins of the scalp and face (p. 646). 



The lingual vein [v. lingualis], begins near the tip of the tongue, where it accompanies the 

 arteria profunda linguae. It lies at first beneath the mucous membrane covering the under 

 surface of the tongue. It then passes backward medial to the hyo-glossus, and in company 

 with the lingual artery. After receiving the sublingual vein [v. sublingualis] and the dorsal 



Fig. 522. — The Internal Jugular Vein. (After Henle). 



Superficial temporal vein 



Frontal vein 



Angular vein 

 Nasal vein 



Branches of the ; 

 anterior facial i 

 vein 



Superior labial 

 vein 



Styloglossus muscle 

 Sublingual gland 



Hyoglossus muscle 



Geniohyoid muscle 



Mylohyoid muscle 

 Anterior cervical vein 



Sternohyoid muscle 

 Thyreohyoid muscle 



Omohyoid muscle 



Temporal vein 



Stylopharyngeus 



Pterygoid plexus 



Superficial branches 



^Styloglossus muscle 



Posterior facial vein 

 Pharyngeal vein 



Stylohyoid muscle 

 Anterior facial vein 

 Common facial vein 



Superior thyreoid vein 



Internal jugular vein 



lingual veins [w. dorsales linguae], wliich roughly correspond to their respective arteries, it is 

 joined by the small v. comitans nervi hypoglossi which follows the upper border of the hypo- 

 glossal nerve. Tlie trunk finally crosses the common carotid artery and opens into the internal 

 jugular vein. The lingual vein communicates with the pliaryngeal veins and with tributaries of 

 the anterior facial. It occasionally terminates in the posterior or in the common facial vein. 

 The sternomastoid vein [v. sternocleidomastoidea] accompanies the artery of the same name and 

 empties into the internal jugular. . ^ i. r it, 



The superior thyreoid vein [v. thyreoidea superior] emerges from the upper part ot the 

 thyreoid gland, in which it freely anastomoses with the other thyreoid veins. This anas- 

 tomosis, the plexus thyreoideus impar, occurs both in the substance of the organ and on its 

 surface beneath the capsule. 'J1ie vein then passes upward and laterally into the internal 

 jugular vein, crossing the common carotid artery in its course. At times it forms a common 

 trunk with the common facial vein. Its tributaries are the sterno-hyoid, sterno-thyreoid, 

 and thyreo-hyoid veins from the muscles bearing those names; and the crico-thyreoid and 

 superior laryngeal veins which correspond with the crico-thyreoid and superior laryngeal arteries 

 respectively. 'I'hese require no special description. 



