306 MEDICAL ENTOMOLOGY 



FAMILY LEPTIDAE 



Flies of moderate or large size with elongated bristly bodies. Vena- 

 tion similar to that of the Tabanidae. Antennae very variable, usually 

 with three joints ; the third may consist of a number of small segments 

 and is with or without a terminal or dorsal arista. Empodium pulvilli- 

 form ; tibiae with spurs. Larvae chiefly aquatic and as a rule predaceous. 



According to Austen there are four blood-sucking species belonging 

 to three genera. Williston states that one of these, Symphormyia, 

 which is found in America, has the habit of sucking blood like the 

 Tabanidae. Its first antennal joint is thickened and elongated, and the 

 third segment is reniform in shape; the hind tibiae have a single 

 spur, and the anal cell is open as in Tabanus. The proboscis is short 

 and stout. 



Two of the other blood-sucking species belong to the genus Leptis, 

 namely, Leptis scolopacea and L. strigosa, both of which are found in 

 France ; they appear only occasionally to suck blood. The hind 

 tibiae of these two flies have two spurs and the third antennal segment 

 is not reniform. 



The fourth blood-sucking species belongs to the genus Trichopalgus, 

 (T. obscurus), and is found in Chili; it is said to have a long pro- 

 jecting proboscis. 



FAMILY PHORIDAE 



Small, often minute, flies with a hunch-backed appearance. The third 

 joint of the antenna is often large, concealing the other segments, and 

 is spherical and often pointed, with an apical or subdorsal arista. The 

 wings are usually large but may be small or entirely wanting. There 

 are two strong veins extending half way to the apex of the wing, and several 

 weaker ones running obliquely across the wing. The larvae usually live on 

 decaying vegetation or animal matter ; some live in ants nests. 



Aphiochaeta ferruginea, Brunetti. Female. Head brownish yellow, 

 tinged with grey ; antennae pale yellow, third joint large as in most of 

 the members of the Phoridae ; arista long and minutely pubescent. 

 The frons has four rows of four bristles. Thorax bright ferruginous 

 or brownish yellow. Abdomen dark ferruginous or brownish yellow ; 

 sometimes it is blackish with a red tinge, altering the general appearance 

 of the fly. It is widely distributed, and has been recorded from most 

 parts of India, Ceylon, Burma, Malay, West Indies and Central 

 America. 



