DISEASES OF THE SKIN. 481 



two or three days only from a singh' invasion, hut will last until cold 

 weather sets in if there is a fresh invasion daily. Ilor.ses at pasture 

 sutler mainly on the lower part of the face. If kept indoors the 

 disease will disappear, or if left at pasture a weak tar water or solu- 

 tion of tobacco may be applied to the face. 



TICKS. 



The wood ticks are familiar to inhabitanls of uncultivat*:'d lands, 

 and prove troublesome parasites to man and beast alike. The tick 

 lives on bushes, and attaches itself to the mammal only to secure 

 «n feast of blood, for when jrorged it drops oil' to sleep (»ir its debauch 

 on the soil. The tick produces j^reat irritation by boring into the 

 skin with its armed proboscis. If pulled out, the head and thorax 

 are often left in the skin. They may be covered with oil to shut 

 out the air from their hivathing jjores, or by touching them with 

 a hot penknife they will be impelled to let go their hold. 



GRUBS IN SKIN. 



Pai^vsite: Ilypoderttui Vmeaiiu Malady: Larvae, {gruhs) under 

 the skin-. — The larva? of a ily (probably Ilypodcrma Unea/d, whose 

 larvic in the skin of cattle are commonly known as *' warbles ") are 

 occasionally found in little sacs beneath the skin of horses. The 

 mature larva escapes in early smnmer and develops into a fly. In 

 districts where they exist the grubs should be jjressed out of the skin 

 in the course of the winter and <lestroyed. 



LARV^ (GRUBS) ON THE SKIN. OR FLYBLOW. 



The following Hies, among others, deposit their eggs on open sores 

 or on wet, filthy parts of the skin, where their larvie or grubs give 

 rise to serious trouble : Luc'dia cit'sar (bluebottle), CochUomyia nuwel- 

 laria (screwworm fly), Musca vo^niforia (meat fly), and Sdrcophu/io 

 caniana (flesh fly). To prevent their attacks, wet, filthy hair should 

 be removed and wounds kept clean and rendered antiseptic by a 

 lotion of carbolic acid 1 part, water .'>0 parts, or by a mixture of 1 

 ounce oil of tar in 20 ounces sweet oil, or by some other antiseptic. 

 If the grubs are already present they should be picked off and one 

 of these dressings freely applied. 



FLIES. 



A number of (lies attack horses and suck their bloo<l. producing 

 great annoyance and in some instances death. These insects not only 

 suck the blood, but also often instill an acid poison into the skin, and 

 in exceptional cases transfer infectious germs from animal to animal 

 by inoculation. 



Various devices are resorted to to prevent the attacks, as to sponge 

 the skin with a decoction of walnut or elder leaves, of tobacco, to dust 

 30441°— 16 31 



