PARASITES OF THE SKIN. 453 



trouble, and the removal of this and a whitewashing with quicklime, 

 with or without chloride of lime, will prevent future attacks. The 

 skin may still require bland ointments or lotions, as for congestion. 



Parasite: Larva of a Tromhidium, Lej)tus americanvs^ or harvest 

 hug, misnamed jigger {chigoe). Malady: Autumn mange. — This 

 parasite is a brick-red acarus, visible to the naked eye on a dark 

 ground, and living on green vegetation in manj^ localities. It attacks 

 man, and the horse, ox, dog, etc., burrowing under the skin and giving 

 rise to small papules and intolerable irritation. This continues for 

 two or three days only if no fresh acari are received, but Avill last 

 until cold weather sets in if a fresh colony is received every day. 

 Horses at pasture suffer mainly on the loAver part of the face. If 

 kept indoors the disease will disappear, or if left at pasture a weak 

 tar-water or solution of tobacco may be applied to the face. 



Parasites: Gamai'us pteroptoides and Cheyletus live in musty fod- 

 ders and are found on the horse. 



TICKS. 



The wood ticks are familiar to inhabitants of uncultivated lands, 

 and i^rove troublesome parasites to man and beast alike. The tick 

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

 a feast of blood, for when gorged it drops off' to sleep off its debauch 

 on the soil. The tick produces great 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 breathing pores, or by touching them with 

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



ORUBS IN SKIN. 



Parasite: Hypoderma lineata. Malady: Larvae, {gruhs) under 

 the skin. — The larvae of a fly (probabl}^ Hyjyoderma lineata, whose 

 larvse 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 summer and develops into a fly. In 

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

 in the course of the winter and destroyed. 



LARV.K (grubs) on THE SKIN, OR FLYBLOW. 



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

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

 rise to serious trouble: Lucilia cmsar (bluebottle), Lucilia homini- 

 vorax (screAvworm fly), Musca vomitoria (meat fly), and Sarcophaga 

 ca7maria (flesh fly). To prevent their attacks, wet, filthy hair should 

 be removed and wounds kept clean and rendered antiseptic b}^ a 

 lotion of carbolic acid 1 part, water 50 parts, or by a mixture of 1 



