SKIN DISEASES. 277 



PARASITIC GREASE. CONTAGIOUS FOOT-ROT IN SHEEP. 



In inflammation of the horse's heel, attended with fungus- 

 like growths {grapes), a vegetable growth is often present and 

 seems to be a main cause of the disease. The contagious foot- 

 rol in sheep presents the same appearance of the skin, and is 

 presumably due to a similar parasite. With or without an 

 abrasion, the matter from a diseased foot produces in the 

 healthy one swelling, excoriation, and fungus growths round 

 the top of the hoof, as well as an excessive growth, softening 

 and loss of cohesion of the horny elements below. 



Pig. ^^_ — Oidium Batracos's fom Parasitic Grease. — Megnin. 



Trealnicnl consists in laying bare the diseased surface, and 

 applying active caustics and parasiticides. Pare the horn to 

 the quick and apply tow soaked in tincture of muriate of iron, 

 butter of antimony, solution of blue-stone or nitrate of silver, 

 bind ui) firmly, and repeat the dressing daily. All overgrown 

 horn must be carefully removed, and means taken to prevent 

 irritation from dried mud, etc. 



MANC.IC. SCAB. ITCH SCABIES. ACARIASIS. 



These names among others are given to diseases of the skin 

 caused by acaii. Of parasitic acari there are three principal 

 species : Sanoplc>, which burrow in canals in the scarfskin and 

 are difficult to find and eradicate, and dermatophagus and dcr- 

 innfocoptis, which live on the surface or among the scabs, and 



