BLOOD-SUCKING NEMATOCERA: SIMULIIDiE 123 



raising a large bump that itches for days ; the bite is not 

 known to carry any specific infection, but Culicoides is one of 

 the insects that has been suspected of inoculating the micro- 

 organism of Delhi boil. 



J ohannseniella is said to differ from Culicoides in having 

 no empodia : the wings are usually bare. 



Family SlMULllD^ (Lat. 5?V«Z(!/z^j = snub-nosed). 



The species of this family (Fig. 29) are small, thickset, 

 unmidgelike flies, with short stout legs, large broad wings, 

 a short and heavy, but formidable proboscis, and short stiff" 



Fig. 29. — Symuliv/m nigrogilvum. 



antennae composed of 10 segments not bearing whorls of 

 hairs. They are very often all black, but may be reddish- 

 brown, or may have the legs conspicuously banded, or the 

 thorax beautifully striped ; and one of the Oriental species 

 is almost as vividly coloured as a wasp. The costal, sub- 

 costal, and 1st and 3rd longitudinal veins (the 2nd longi- 

 tudinal vein is absent) are stout and bristly, but the other 

 longitudinal veins, which are forked, are faint to the verge 

 of invisibility ; the costal vein ends at the tip of the wing. 

 The mouth-parts of the female are formed for stabbing and 

 cutting (Fig. 30) ; in general they resemble those of the 

 female gadfly but are, for their size, even more formidable ; 

 the epipharynx is armed at its tip with recurved booklets, 

 and the mandibles and maxillae are shaped like lancets, the 



