XVIII. Family NKMISTRINIDjE. 



Species of moderate size, not elongate, thinly or densely 

 pilose. Venation complicated; the fourth and fifth veins 

 are curved forward to terminate before the tip of the wing; 

 the anterior cross-vein is obsolete, that is the third and 

 fourth veins coalesce for a short distance; basal cells 

 long. Antennae small, short; third joint simple, with a 

 terminal, slender, jointed style. Proboscis sometimes 

 elongate. Ovipositor of the female elongate, often slen- 

 der. Tibiae without spurs; empodia developed pulvilli- 

 form, but, with the pulvilli often minute. (See fig. 69.) 



Fig. 68. Wing of Rhynchocephalus volaticus. 

 a, third submarginal cell; b—f, first— fifth posterior cells. 



Throughout the world about one hundred species of 

 this family are known, the larger part of which are from 

 South America and Australia. Only six species are 

 known from North America and two or three from all 

 Europe. Some of the species have the wings with nu- 

 merous cross-veins, almost recticulate in appearance. 

 Megistorhynchus longirostris from Africa, though only 

 about two-thirds of an inch in length, has a proboscis 

 nearly three inches long. The adults are flower flies, 

 resembling in their habits the Bombyliidae. 



But little is known of the larvae. The females of Hir- 

 moneura obscura have been observed laying their eggs 

 deeply within the burrows of Anthaxia, a wood-boring 



1S6 



