BOMBYLIN^ 483 



BOMBYLINiE. 



Prgefurca short, ending almost opposite the base of the discal cell. 

 Antennse approximated at the base. Proboscis usually long and porrect. 

 Abdomen short and rounded. 



Head rather small and rounded, rarely (Lasioprosopa, Corsomyza) transverse and 

 wider than the thorax, considerably puffed out behind the eyes but without bristles. 

 Proboscis conspicuously long and horny (except in Glahellula and Platypygus), with 

 very small sucker-flaps. Eyes approximated or touching in the male, or when 

 widely separated {Glabellula, PJatypyijm, Usia) then the abdomen short and broad ; 

 eyes with no indentation at the middle of the hindmargin. Antennae approximated 

 at the base ; basal joint not specially long nor bare ; style variable. 



Thorax arched and often humpbacked, usually clothed with dense furry 

 pubescence, but sometimes with few hairs, or even bare in those species which 

 have a simple cixbital vein. 



Abdomen short and broad, rarely conical, often clothed with dense furry 

 pubescence but sometimes bare. 



Legs thin, sometimes bare, but often with stickdike spines beneath the femora 

 and with spicules and a circlet of terminal spines on the tibiae. Pulvilli two as in 

 all Tromoptera, unless it be correct that Cyrtosia has three. 



Wings (fig. 270) with the radial and cubital veins leaving the short praefurca at 

 an almost equal very acute angle which is almost opposite the base of the discal 

 cell ; subcostal vein comparatively short ; radial vein never looped before its end, 

 but in Ploas (fig. 278) drawn back by the adventitious connecting veinlet and 

 ending rectangularly in the costa ; cubital fork usually short and wide open (but 

 not in Phthiria or Usid) ; submarginal cells one, two, or three ; posterior cells four 

 o^' three ; anal cell oi^en or closed. 



The Bomhylince are easily distinguished from the Anthracince by the 

 short prsefurca and usually by the radial and cubital veins diverging from 

 the prsefurca at an acute angle long before the discal cross-vein ; from the 

 Toxophorincc and Systropince by the short rounded abdomen ; and from the 

 Lomatince (which are the nearest allies) by the rounder abdomen (except 

 perhaps in Oligodranes), by the longer proboscis, and usually by the less 

 looped or upturned radial vein. The species with the simple cubital vein 

 will probably form a separate subfamily distinguished by almost total 

 bareness, humped figure, and (except in Cyrtosia) short proboscis. 



TaUe of Palccarctic Genera of ^OMWiW^M. 



1 (8) One submarginal cell, the cubital vein (if present) being not 



forked. 



Extremely humpbacked, al- 

 most or quite bare flies, somewhat 

 like Cyrtidce. 



2 (5) Eadial vein practically absent. 



3 (4) Proboscis short. 



Second basal cell very large, ^lo. 27i. -GiabdUda Ma Zett. 6. 



emitting two simple veins in 

 addition to the two branches of the postical vein (fig. 271). 



One little known arctic species. 



Glabellula. 



