DISEASES OF THE SKIN. — EXTERNAL PARASITES. 209. 



atrophied by compression ; but smooth, not ulcerated, and 

 either quite dry or moist from serous exudation ; sometimes 

 it is pale and anaemic ; but more frequently red, irritated, 

 and sufificiently transparent to show some very fine blood- 

 vessels. Around the margin of the crust the skin is sensibly 

 inflamed, red, thickened, and rises into a somewhat salient 

 prominence. In the dog there is much pruritis : a symptom 

 which is rarely noticeable in the cat ; otherwise, it does not 

 appear to exercise any prejudicial effect on the general 

 health. 



" Another form is that in which the plant is found in de- 

 pressions on the surface of the skin, forming the yellow 

 honeycomb-like masses which gave the name ' f avus ' to the 

 disease, and which, from their being frequently buckle-shaped, 

 suggested the term ' scutulata.' A cuticular elevation is 

 seen, beneath which is a small favus. Generally there is no 

 pus or fluid of any kind ; the fungus grows, and the cuticle 

 above it, supposing it to have become forcibly detached, 

 Hnally separates, leaving the favus exposed."* 



Treatment. — With regard to curative measures the same 

 able writer observes ; " The crusts should be removed by 

 alkaline vvashes^hyposulphite of soda, or raising them by 

 means of a spatula or the blunt extremity of curved scissors, 

 taking care not to make the part bleed. When the skin has 

 been cleansed in this manner as much as possible, a concen- 

 trated solution of corrosive sublimate (one to five of the sub- 

 limate to fifty of distilled water) should be applied every day. 

 After the first application, the favus crusts sometimes have a 

 tendency to be reproduced, and the cryptogamic elements to 

 multiply. In such a case, it is necessary again to remove the 

 crusts, as at first. Five or six dressings are usually suificient. 

 At times, however, and especially when the disease is seated 

 at the base of the claw (as in the cat), they must be continued 

 for a longer period. Under the influence of this treatment, 

 the skin, which is depressed on its surface, is not long before 

 * Fleming's " Veterinary Sanitary Science," vol. ii. pp. 474. 47S- 

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