ASILIDiE 



619 



cell and humpbacked thorax. The subfamilies of the Asilidce may some 

 day be founded on more natural characters, as Zaphria-hke species occur 

 unnaturally in quite the middle of the Asilinoe or Dasypogonince, and 

 many abrupt contrasts exist in the present arrangement ; the general line 

 of development from Apioceridce to Empidce seems however to be a 

 natural one. 



Type of venation of the AsiLiD^. 



Fig. %Z9.—Asilus crdbroniformis 9 • 



Longitudinal {or long) veins. 



a Costa {or costal vein). 



h Mediastinal {or auxiliary) vein. 



c Subcostal {or 1st longitudinal) vein. 



d Radial {or 2nd longitudinal) vein, ending in the subcostal vein in the Asilinm 



and Laphrinoe. 

 e Cubital {or Zrd longitudinal) vein. 



el Upper branchj ^^ ^^^ ^^^-^^j f^^],_ 



e^ Lower branch J 

 / Discal {or Ath longituditml) vein. 



fi Upper veinlet 1 



f2 Second, veinlet Vfrom the discal cell. 



P Third veinlet J 

 g Postical {or 5th longitudinal) vein. 



gi Upper branch j ^^ ^^^ ^^^^^^^^ fork. 



g^ Lower branch J 

 h Anal (or 6th longitudinal) vein. 

 i Axillary vein. 

 A- Pr8efarca = the common stem of the radial and cubital veins. 



Ambient vein = the continuation of the costal vein round the hindmargin of the 

 wing. 



Cross {or transverse) veins. 



tv Humeral cross-vein. 



X Discal {or middle) cross-vein. 



y Lower {or small) cross-vein. 



Anal cross-vein =g2 = the lower branch of the postical vein. 



