TABLE OF FAMILIES OF DIPTERA. 377 



2. Costal vein attenuated to hind margin. 

 * Alulae very large. 



Tabanidse. (Horseflies.) Antennae six, 



eight, or ten joints ; joints unequal. 

 ** Alulae very small. 



Xylophagidaa. Proboscis withdrawn ; an- 

 tennae ten joints ; joints equal after 

 second, and cylindrical, or tapering. 

 Asilidse. Foot-pads very large,f forehead 

 hollowed. Antennae three or five 

 joints, unequal. 



Leptid. Empodium dilated like foot- 

 pads ; forehead convex ; antennae gene- 

 rally three joints, third largest, trans- 

 verse or conical, or bearing a bristle. 

 Bombylidas. (Beeflies.) Empodium slen- 

 der, pointed; forehead convex; antenna 

 three or four joints, unequal 

 b. Cubital vein simple. 



1. Axillary lobe of wing obsolete. 

 * Tip of wing rounded. 



Empidae. Brachial and anal areolets, some 

 of them reaching to one-third of wing ; 

 abdomen seven or eight segments. 



Dolichopidae. Brachial and anal areolets 

 minute or indistinct ; abdomen five 

 segments, or in $ 6, rarely seven. 

 ** Tip of wing pointed. 



Lonchopteridae. 



2. Brachial veins each accompanied by spu- 



rious veins. 

 Syrphidae (Droneflies, &c.) 



t Except in one genus, Leptogaster, to be recognised by the absence of 

 foot-pads. 



