2IO DURHAM DIPTERA. 



XXXI. 



14 (8) (13). Abdomen with four segments, short, oval, or 



conical, seldom cylindrical, but in the latter 

 case not bent inwards behind, and the genitalia 

 not prominent. 



15 (72). 0.4 2 ending very far before, or rather far before, the 



tip of the wing, generally open and never long 

 stalked ; or, if 0.4 2 ends rather near the tip, and 

 so this character is doubtful, then either X.5 2 is 

 much nearer to the bend of V.4. than to X.4. ; or, 

 the arista is almost quite bare ; or, V.3. is either 

 straight or bent upwards to the fore margin, so 

 that 0.3. is not widened out at the end, and is 

 throughout always narrow. 



16 (65). Facial bristles absent, at most a few near the mouth, 



but not reaching up beyond half-way to the base 

 of the antennae. 



17 (42). Eyes bare. 0.4 2 open. 



18 (19). The third antennal joint shorter than the much 



lengthened second. Echinomyia, Dum. (380) 



19 (18). The third antennal joint as long as, or longer than, 



the second. 



20 (23). Arista three-jointed and geniculated, each joint is 



therefore very distinct. 



21 (22). Head, and especially the frons, inflated, and very 



large. Gonia, Mg. (353) 



22 (21). Head not inflated. 



352. Germaria, Dsv. (1726. ruficefis, Fin.) 



23 (20). Arista two-jointed, or, if three-jointed, then not geni- 



culated. 



24 (25). X.5 2 much inclined outwards, its base below X.4. 



and its end slightly nearer to the bend of V.4 

 than to X.4. Plagia, Mg. (384) 



25 (24). X.5 2 never very much inclined, its base always beyond 



X.4., and its end distinctly nearer to the V.4. bend 

 than to X.4. 



26 (35). The third antennal joint as long, or at most twice as 



long as the second. 



