DISEASES OF THE SKIN. 481 
two or three days only from a single invasion, but will last until cold 
weather sets in if there is a fresh invasion daily. Horses at pasture 
suffer 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 inhabitants of uncultivated lands, 
and prove 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. 
GRUBS IN SKIN. 
Parasite: Hypoderma lineata. Matavy: Larve (grubs) under 
the skin.—The larve of a fly (probably Hypoderma lineata, whose 
larve 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. 
LARV4S (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 larve or grubs give 
rise.to serious trouble: Lucilia cesar (bluebottle), Cochliomyia macel- 
laria (screwworm fly), Musca vomitoria (meat fly), and Sarcophaga 
carnaria (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 50 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 flies attack horses and suck their blood, 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 
jn 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 
86444°—16——31 
