264 HEAD AND NECK 



antero-medial surface is directed anteriorly and lies in relation 

 with the lower part of the posterior border of the internal 

 pterygoid, the stylo-mandibular ligament, and the posterior 

 border of the ramus of the mandible. The more lateral part is 

 directed medially and rests against the lateral surface of the 

 masseter. This surface is pierced (i) by the external carotid 

 artery, (2) the posterior facial and the internal maxillary veins, 

 (3) all the terminal branches of the facial nerve except the 

 cervical, and (4) by the duct of the gland. 



As the dissector examines the parotid space he will note 

 that as the external carotid disappears under cover of the 



Anterior border 



of upper extremity 



Posterior facial vein 

 Area for neck of mandible 1 

 Transverse facial artery 



Superficial temporal artery- 

 Internal maxillary artery - 



Internal maxillary ^ 



Anterior border 



External jugular vein --T& 



^U 



Posterior facial vein ~--fcJ External carotid artery 

 FIG. 109. Parotid Gland, antero-medial aspect. 



posterior belly of the digastric it is placed so far anteriorly 

 that it is also under cover of the posterior border of the 

 mandible ; and it does not emerge from under cover of the 

 mandible until it reaches the level of the neck of the bone, 

 where it appears on the antero - medial surface of the 

 gland and divides into its two terminal branches. Further, 

 he will now readily recognise the impossibility of studying 

 the upper end of the cervical part of the internal carotid, 

 the upper part of the internal jugular vein, and the last 

 four cerebral nerves, until he is in a position to reflect the 

 posterior belly of the digastric and the styloid process ; and 

 as both of them are, to a certain extent, under cover of the 



