40 PRACTICAL ANATOMY. 



The parotid gland (Fig. 20) is located by limitation : 



1. Superiorly, limited by the zygomatic arch. 



2. Inferiorly, limited by the angle of the mandible. 



3. Anteriorly, limited by the mid-line of the masseter. 



4. Posteriorly, limited by the mastoid process and sterno-mastoid. 



5. It sends in prolongations as follows (Fig. 19) : 



The inner surface is irregular, sending (i) a large process of gland tissue, in 

 front of the styloid process of the temporal bone, the same also occupying the 

 non-articular part of the glenoid cavity ; (2) a large process behind the styloid 

 and under the mastoid process and sterno-cleido-mastoid muscle. 



Parotid fascia is the name given to the deep fascia covering the outer sur- 



PALATINE PROCESS OF SUPERIOR 

 MAXILLA 



ZYGOMATIC ARCH 



HORIZONTAL PLATE OF PALATE BONE 



GLENOID FOSSA 



rrnlid Gland 



STVLOID PROCESS 

 Parotid Gland 



MASTOID PROCESS 



FIG. 19. SHOWING SCHEMATICALLY THE DEEP PART OK THE PAROTID GLAND EMBRACING 



THE STYLOID PROCKSS. 



face of this gland. You have already cut through the gland vertically to find 

 the seventh nerve. 



Contents of the Parotid Gland : 



1. The facial nerve and pes anserinus. 



2. The auricula-temporal branch of the fifth nerve. 



3. The external carotid artery and its three terminals. 



4. The posterior auricular, temporal, and transverse facial arteries. 



5. The internal maxillary artery and vein. 



6. The temporo-inaxillary vein. 



7. A branch of the great auricular nerve to the seventh. 



Excretory Duct of the Parotid (Fig. 20). Stenson's duct crosses the 

 masseter muscle on a line from the centre of the upper lip to the lobule of the 

 ear. It perforates the buccinator muscle, and opens into the vestibule of the 

 oral cavity, opposite the second upper molar tooth. 



