EXTERNAL CANKER 433 



edf^e of the external ear, generally at its extreme end, an ulcer or a 

 number of them which are covered with a blackish loose scab with 

 turned-up edges, and the tissues of the immediate neighborhood are 

 oedematous. 



Therapeutic Treatment. — The first procedure is to ascertain if there 

 are any evidences of internal otitis; if so, heal that and lessen the irritation 

 and itching. Xext prepare an ear-cap (Fig. 152), which is so very 

 essential in this affection. Dress the inflamed edges first with an anti- 

 septic solution and get all the scab-dirt, broken down tissue and hair 

 away, then paint the edges with compound tincture of benzoin and 

 apply this daily, keeping on the ear-cap. Other ointments, such as airol, 

 benzoin and lanolin, or stimulant counter-irritants, such as iodine or 



nitrate of silver may be employed. The writer has found the following 

 method very efficacious : Clean the ear thoroughly, then apply freely 

 some drj'ing powder, such as dermatol or boric acid, on both sides and 

 the edges of the ear. Have prepared an oblong piece of linen or muslin 

 as in the accompanj-ing illustrations (Figs. 154, 155) , cover this with liquid 

 glue and apply it as seen in the Fig. 155; this is held in position until dr>-. 

 When it is to be removed the ear can be steeped in warm water and it is 

 easily removed. It is best, however, to let it remain until it falls off, as 

 by that time the ulcers have healed and the scabs and hair come off with 

 the bandages. In very small animals silicate of soda solution or rubber 

 adhesive plaster can be substituted for glue, but in ordinary- sized dogs 

 the glue is the most efficacious. When there are a series of deep tears 

 or chronic separations of the ears, and the edges of the ears are in a 

 chronic state of inflammation, with more or less induration of the tissue, 

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