PARASITES OF FLIES 233 



CHAPTER XXIV 



PARASITES OF FLIES 



(A) External parasites of adult flies. Mites. 



Small reddish mites are often found attached to the bodies 

 of different kinds of flies. Unless very numerous they do not 

 appear to affect the health of the fly, which usually seems to be 

 oblivious of their presence. Mr Nathan Banks, an authority 

 upon this group of creatures, gave Howard the following 

 interesting information. 



Fig. 25. Mite from Stomoxys caldtrans ( x 50). 



" Latreille based a new genus and species on mites from the 

 house-fly, and he called it Atomus parasiticitm. This is the 

 young of one of the harvest mites of the family TrombidiidcB, but 

 the adult has not been reared, and is still unrecognized in Europe. 

 Riley found these harvest mites on house-flies in Missouri, in 

 some years so abundantly, he says, that scarcely a fly could be 

 caught that was not infested with some of them clinging tena- 

 ciously at the base of the wings. Later he succeeded in rearing 

 the adult, and described it as Trombidiinii mnscarum. All these 

 forms are minute, six legged, red mites which cling to the body 

 of the fly and with their thread-like mandibles suck up the 



