39 6 7 
4. Base of proboscis suddenly expanded into a 
large onion-shaped bulb. 
5. Arista feathered on upper side only. 
Fig. 125A. 
(2). Stomoxys calcitrans. Transverse section through about the middle 
of the proboscis. The hypopharynx is kept in its place by the projecting 
ends of the labrum. The interlocking teeth of the lahrum and labium 
are also shewn 
6. Male genitalia (hypopygium) highly charac¬ 
teristic, oval and tumid, with a vulviform median 
groove (anus) running from anterior margin to beyond 
the middle. Sex easily distinguished by this mark. 
7. Wings absolutely characteristic, especially in 
the course of the fourth longitudinal vein (vide Fig. 
