492 THE ANIMAL PARASITES OF MAN 



Genus. Dermanyssus, Duges. 

 Dermanyssus gallinae, de Geer, 1778. 



Syn. : Pulex, gallince, Redi, 1674; Atarus galliruz, de Geer, 1778 ; 

 Dermanyssus avium, Duges, 1834. 



The male measures 0*6 mm. in length by 0*32 mm. in breadth; the 

 female 07 to 075 mm. in length by 0-4 mm. in breadth. The body 

 is somewhat pear-shaped ; the colour whitish, reddish, or reddish- 

 black, according to the contents of the intestine. The legs are 

 fairly short and strong. During the day they live concealed in the 

 nests, cracks, etc., of the hen-house, and at night attack the inmates 

 in order to suck their blood ; they rarely remain long on the birds. 

 They have been repeatedly found on persons, on whose skin they 

 produce an itching eruption. 



Dermanyssus hirundinis, Hermann, 1804. 

 Syn.: Acarus hirundi?iis, Herm., 1804. 



Of a brownish colour, i'2 or 1*4 mm. in length ; lives in the riests 

 of swallows and is occasionally found on man. 



[The red hen mite (Dermanyssus galUnce) not only attacks 

 poultry and man, as stated above, but is found on all birds and 



FIG. 358. Dermanyssus hirundinis. 

 FIG. 357. Dermanyssus gallina. En- 4/i- (After Delafond.) 



larged. (After Berlese.) 



many mammals. The D. gallince is the same as D. avium. The 

 species found in swallows' nests is also said to be the same. This 

 mite can remain for weeks without any food from its normal 

 host. They only attack man when entering or cleaning dirty and 

 neglected fowl-houses ; they do not produce a true dermatosis. They 

 chiefly attack the backs of the hands and forearms of those who con- 

 stantly attend poultry and give rise to symptoms similar to the 

 papular eczema of scabies. That they may remain some time upon 



