280 
Sarcoptic Scabies 
Equi. 
Tierreich : Gerlach, 1857 (von Hering, 1838). 
Dorsal scales small, scarcely longer than broad; an anterior and a posterior 
rugose area; notogastral spines blunt; notothoracic cones very short; epiandrium 
scarcely reaches the epimere. 
$ 450-500/x x 310-370/z. 
<J 230-280/x x 150-200/x. 
Horse, but can flourish on ass, mule and man for a short time. 
This form was independently discovered by Gerlach and Delafond simul¬ 
taneously. It is the cause of “dry mange,” “symptomatic mange,” or 
“epizootic mange” in the Equidae (Gerlach, 1857, p. 116, Pl. II, figs. 8-10). 
Text-figure 4. Sarcoptes equi, according to Railliet. 
Gerlach says the $ is somewhat longer and narrower than the human Sarcoptes , 
but is only to be distinguished when seen in the bulk; his measurements of 
the $ (reduced from fractions of an inch to microns) are 440 x 300/z. 
Delafond and Bourguignon remark that the “solipedes” have two mange 
parasites, a Sarcoptes and a Psoroptes, the former transmissible to man, the 
latter not. (There is also a Chorioptic scabies of the horse.) 
Neumann (p. 131) says “Sarcoptic scabies begins most frequently at the 
withers, and extends to the sides of the neck, shoulders, back and sides. It 
does not easily invade the extremity of the limbs, and it respects the parts 
covered with strong hairs. The Psoropt, on the contrary, appears to seek the 
parts avoided by the Sarcopt.” 
