Diseases Affecting the Skin 231 



the surface of the skin, or, at anyrate, in galleries 

 beneath the superficial layer of the epidermis. These 

 parasites set up a good deal of irritation, which 

 may be accepted as one of the earliest indications 

 of the disease. The male acari are much smaller 

 than the females, and nothing like so numerous, but 

 the latter are very prolific, so that the species is 

 freely perpetuated. A pregnant female may rapidly 

 spread the disease over the body, but the destruction 

 of the parasites or their ova, if such be complete, 

 puts an end to the disease; but mange is often of a 

 very recurrent nature, perhaps less so than in the 

 horse. Sarcoptic mange is not, as a rule, a difficult 

 disease to cure, but its infective nature renders it 

 very liable to contaminate a whole pack of hounds, 

 if reasonable means are not adopted to prevent its 

 transmission from one dog to another. Mange in 

 the fox is apparently due to a different species of 

 parasite, but whether it can be communicated from 

 this animal to the dog is doubtful. Infection may 

 be direct or indirect; by direct infection we mean 

 the contact of the diseased with the healthy; in- 

 direct, on the other hand, through some other media, 

 such as collars, brushes, clothing, kennel fittings, 

 bedding, feeding- vessels, etc. One mangy dog may 

 in a locality transmit the disease to a large proportion 

 of other dogs in the same or other locaUties, and 

 hence the difficulty in fixing the original source of 



