PARASITES AFFECTING THE SKIN 33 
Treatment consists in passing the animals through a 
trough containing copper sulphate solution, and in- 
unction of parts above the knee and hock with creolin 
ointment. 
This form of mange is very amenable to treatment. 
NON-PSORIC ACARIASIS. 
The non-psoric Acari comprise the Ixodide, or ticks, 
and the Trombidiide, or running mites. The Ixodide 
are by far the larger and more important group. They 
are large insects, macroscopic, and live in coarse grass 
and undergrowth. Dirty farms, with rough herbage, 
moorland, and untrimmed hedges, provide their ideal 
habitat. 
Ticks have flat bodies, protected by horny shields 
on both their dorsal and ventral surfaces. They are 
blood-suckers, and pass the parasitic portion of their 
existence on the bodies, chiefly on the limbs, of animals, 
on which they gorge themselves with blood until spherical 
in shape. 
The rostrum is composed of two barbed harpoons 
above and below a dart. In the middle is a sucking 
mouth. The anus is near the mouth, and when oviposit- 
ing, the eggs form clusters round the anterior extremity 
of the parasite. The feet terminate in hooks, for cling- 
ing. The larve possess great vitality, and can live 
many weeks without food. The adult females are very 
prolific, and may produce three broods in one year. 
There are two divisions of the Ixodide—viz., Rhipi- 
cephalus and Ixodes. In Rhipicephalus, or, as it is 
sometimes called, Boophilus, the rostrum is broad and 
the body rounded ; the legs are all inserted within a 
short distance from the head, and the tick possesses 
a pair of eyes. 
In Ixodes the rostrum is long and fine and eyes are 
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