FAMILY DROSOPHILIDAE 311 



Mackinnon has recorded Herpetomonas muscae domesticae, Burnett, 

 from Scatophaga lutaria in England ; in this case the parasite was 

 found in the larvae as well as in the imagines. 



FAMILY BORBORIDAE 



Small to very small brown to black flies. Head hemispherical ; antenna 

 short with the third joint rounded ; arista bare or pubescent. Subcostal 

 vein wanting or if present indistinct. Legs long and well developed ; 

 hind metatarsi dilated and shorter than the next joint. 



This family contains, in addition to others, the two genera Borborus 

 and Sphaerocera, the species of which may be seen in swarms about 

 dung and other refuse. In Madras, a small Borborus, which is very 

 common on cow dung, is nearly always infected with a species of 

 herpetomonas. According to Chatton, Sphaerocera subsultans in France 

 is infected with a species of herpetomonas, H. legerorum. Another 

 borborid belonging to the genus Limosina, L. hirtula, is also infected 

 with a similar flagellate. 



All the above dung flies can be bred out by collecting their larvae and 

 placing them in some fresh dung in a large tray ; when about to pupate 

 the larvae as a rule do not migrate, so that the pupae 

 are found in the dung. If cow dung is collected in a Breeding technil ue 

 heap under a tree and regularly replenished large numbers of sepsids 

 and borborids will soon collect on it, and their larvae can be obtained 

 in a few days. The pupae should be placed in a breeding jar, such 

 as that described further on in connection with the breeding of the 

 Muscidae ; when the flies hatch out they may be fed on fresh cow dung ; 

 the larvae, as well as the imagines, should be examined for flagellates. 



FAMILY DROSOPHILIDAE 



Small stumpy flies usually with characteristic red eyes. Antenna with 

 the third joint oval ; arista plumose with long but scanty hairs. 

 Abdomen short. Subcostal vein absent or indistinct ; first longitudinal 

 vein short ; basal and anal cells not distinct. 



The Drosophilidae are also of interest on account of the natural flagel- 

 lates which some species may harbour. In all parts of the world they are 

 common about fruit, and the fermenting refuse which collects around 

 wine vats. Though popularly spoken of as Fruit Flies, the Drosophilidae 

 should not be confused with the Trypetidae, the well-known fruit 



