29G 



THE BOG IX DISEASE. 



as we know it is bitter and sticky, and is admirably adapted 

 to resist wet, etc. 



FIG. 21. SECTION THROUGH AUDITORY ORGAN (AFTER SAPPEY). 

 1, pinna ; 2, 4, 5, cavity of concha, external and auditory meatus with opening of 

 ceruminous glands ; 6, membrana tympani ; 7, anterior part of incus ; 8, mal- 

 leus ; 9, long handle of malleus, attached to internal surface of tympanic mem- 

 brane it is here represented as strongly indrawn ; 10, tensor tympani muscle; 

 11, tympanic cavity ; 12, Eustachian tube ; 13, superior semicircular canal ; 14, 

 posterior semicircular canal ; 15, external semicircular canal ; 16, cochlea ; 17, 

 internal auditory meatus ; 18, facial nerve ; 19, large petrosal nerve ; 20, ves- 

 tibular branch of auditory nerve ; 21, cochlear branch of same. Though this 

 cut refers especially to man, the relations of parts are essentially the same in 

 the dog. 



Canker, or disease of the external ear, is very common 

 in the dog more so than in any of our domestic animals. 



The exterior of the ear-flap may be the seat of various 

 forms of disease independently of other parts, such as 

 eczema, or it may become affected by extension of disease 

 from within. The treatment in such case is little different 

 from that of any other portion of the body when similarly 

 disordered. Canker is an inflammation of the inner part of 



