688 THE VEINS. 



B. Posterior Auricular Vein. — A voluminous vessel which commences 

 on the concha, and descends on the external face of the parotid gland, near its 

 posterior border, where it is joined by numerous divisions from the parotid 

 lobules. It opens into the jugular vein, generally a little below, and opposite to, 

 the maxillo-muscular vessels, though it is sometimes lower — often even after the 

 occipital vein (Fig. 385, 13). 



C. Occipital vein. — The occipital vein corresponds, in every respect, to its 

 fellow-artery. It has two roots — an anterior, which originates at the posterior 

 extremity of the subsphenoidal confluent ; and a posterior, commencing beneath 

 the transverse process of the atlas, and formed by three principal branches. 



Among the branches of the latter root, one passes with the retrograde artery 

 through the posterior foramen of the atlas, and constitutes, as it were, the origin 

 of the vertebral vein ; the second communicates with the occipito-atloid sinuses, 

 by traversing the atlas near its middle ; the third — satellite of the cerebro-spinal 

 artery — comes also from these sinuses, and receives the venules which accompany 

 the ramifications of the occipito-muscular artery. 



D. Sub-maxillary or Facial Vein. — A satellite of the artery of the same 

 name, this vessel begins on the forehead by two roots — a superior and inferior, 

 analogous in every point to the terminal branches of the artery. It descends 

 along the anterior border of the masseter muscle, gains the maxillary fissure, 

 into which it is inflected, placing itseK between the artery and Steno's duct ; then 

 proceeds backwards and downwards on the internal pterygoid muscle, always 

 accompanied by the glosso-facial artery until near the anterior extremity of the 

 maxillary gland, when it leaves it to follow the inferior border of that gland, and 

 enters the jugular vein, after crossing the sterno-maxillaris muscle outwardly, and 

 forming with the latter vein an angle which is occupied by the inferior extremity 

 of the parotid gland (Fig. 385). 



Branches of origin. — Of the two branches which, by their union, constitute the 

 origin of the submaxillary vein, the inferior {dorsalis nasi) — a satellite of the 

 nasal branch of the corresponding artery — possesses no interest. The superior, 

 or angular vein of the eye, merits particular notice, as venesection is sometimes 

 practised on it. It arises near the nasal angle of the eye, and creeps to the 

 external face of the elevator muscle of the upper lip, below the lachrymalis 

 muscle. 



Collateral branches. — In its progress, the submaxillary vein receives a great 

 number of affluents, the principal of which are the alveolar vein, the labial or 

 coronary veins, the buccal vein, and the sablinguaJ vein. 



a. Alveolar vein (vena varicosa). — This is a considerable vessel lodged beneath 

 the masseter, and lying against the supermaxillary bone, between the zygomatic 

 crest and the aveoli of the upper molar teeth (Fig. 385). 



The arrangement of this vessel is most singular ; its anterior extremity opens 

 into the submaxillary vein, and its posterior extremity traverses the ocular 

 sheath, receives the ophthalmic veins, and passes, with the ophthalmic nerve of 

 the fifth pair, into the foramen lacerum orbitale, to open into the cavernous sinus 

 in the interior of the cranium.^ 



Before traversing the ocular sheath, and towards the maxillary hiatus, this 

 vein receives the superior dental and the confluent of the tiasal veins — vessels 



' We have also seen it send into the subsphenoidal canal, to the inner side of the internal 

 maxillary artery, a slender branch that joined the anterior extremity of the subsphenoidal con- 

 fluent. But we cannot say that this disposition is constant. 



