14 VETERINARY PARASITOLOGY 
Prognosis should be guarded, as the disease often 
resists treatment, and relapse is very common. It is 
extremely difficult to impress upon owners and stable- 
men the necessity of absolute disinfection of harness,rugs, 
and grooming utensils, and the prevention of reinfection. 
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Fic, 3.—Psoroptes Equi (MALE): DorsaL SURFACE 
Psoroptic Mange in Horses.—The parasite responsible 
is the Psoropies communis, var. equi. This form of 
mange attacks sheltered positions, as the mane and tail, 
the intermaxillary space, the breast, sheath, and inner 
side of the arm and thigh. It does not extend below 
the knees and hocks, but may occasionally occur on 
