62 SURGICAL APPLIED ANATOMY. [Chap. v. 



cerumiiious glands, which secrete the cerumen of the 

 ear, and which, when their secretion is excessive, 

 may produce the plugs of wax that often block the 

 meatus. There are neither hairs nor glands in the 

 lining of the bony part of the tube. 



The skin of the meatus, when inflamed, may pro- 

 duce an extensive muco - purulent discharge otitis 

 externa. Polypi are apt to grow from the soft parts 

 of the canal, and exostoses from its bony wall. 

 Foreign bodies are frequently lodged in the meatus, 

 and often involve great difficulties in their extraction. 

 It would appear that in many cases more damage is 

 done by the surgeon than by the intruding substance. 

 Mason reports three cases where a piece of slate-pencil, 

 a cherry-stone, and a piece of cedar-wood were lodged 

 in the canal for respectively forty years, sixty years, 

 and thirty years. 



The upper wall of the meatus is in relation 

 with the cranial cavity, from which it is only 

 separated by a thin layer of bone. Thus, abscess or 

 bone disease in this part may readily lead to menin- 

 gitis. A case is reported where an inflammation of 

 the cerebral membrane followed upon the retention of 

 a bean within the meatus. The anterior wall of the 

 canal is in relation with the temporo-maxillary joint 

 and with part of the parotid gland. This may serve 

 in one way to explain the pain often felt in moving 

 the jaw when the meatus is inflamed, although, at the 

 same time, it must be remembered that movement of 

 the lower maxilla produces a movement in the carti- 

 laginous meatus, and that both the canal and the joint 

 are supplied by the same nerve (the auriculo-temporal). 

 From its relation to the condyle of the jaw, it follows 

 that this wall of the meatus has been fractured by 

 that condyle in falls upon the chin. Tillaux states 

 that abscess in the parotid gland may spread into the 

 meatus through the anterior wall of the passage. 



