TABLE FOR DETERMINING THE GENERA. 45 



/• Antemiw 14- (sometimes apparently 15-) joiuted (Section I. Limno- 



4 J bina). 9 

 ' Antennae 16-jointe(i.' 5 

 f The first longitudinal vein ends in the costa ; tibise without spurs at 

 I the tip (Section II. Limnobiua anomala). 13 



5 \ The first longitudinal vein is usually incurved towards the second 



and ends in it ; tibiae always with spurs at the tip (Section Vll. 

 L Cylindrotomina). 43 



^ ( Tibiye without spurs at the tip (Section III. Eriopterina). 22 



( Tibiae with spurs at the tip.^ 7 



r Subcostal cross-vein posterior to the origin of the second longitudinal 



- J vein. 8 



I Subcostal cross-vein anterior to the origin of the second longitudinal 

 I, vein ; Tab. II, fig. 14-18 (Section VI. Amalopina). 38 



„( Antennse 16-jointed (Section IV. Limnophilina). 32 



( Antennae from 6- to 10-jointed (Section V. Anisomerina). 35 



Section I. Limnobina. 



Proboscis longer than the head and thorax taken together. 



Gen. II. Gekanomyia. 



( Proboscis not longer than the head. 10 



,^ J Antennae pectinate or subpectinate. Gen. III. Reipidia 



I 



{ 



12, 



Antennaj of the ordinary structure. 11 



(A cross-vein unites the sixth and the seventh longitudinal veins. 

 11 < Gen. V. Tkocuobola. 



^ No cross-vein between the sixth and the seventh longitudinal veins. 12 

 The forceps of the male consists of two movable fleshy lobes ; tip of 

 the auxiliary vein usually opposite, or anterior, or only a short 

 distance posterior to the origin of the second vein ; marginal 

 cross-vein always at the tip of the first longitudinal vein ; feet 

 slender. Gen. I. Dicranomyia. 



The forceps of the male consists of two horny hooks ; tip of the aux- 

 iliary vein usually far beyond the origin of the second vein ; 

 marginal cross-vein sometimes at the tip, but often some distance 

 before the tip of the first longitudinal vein ; feet comparatively 

 stout. Gen. IV. Limnobia. 



' In Elephantoiiu/ia the antennae are 15-, in Toxorrhina 12-jointed; :n 

 both cases through the evident coalescence of several joints at the basis 

 of the flagellum ; but as both genera have a rostrum which is nearly as 

 long as the body, they will not easily be mistaken. 



2 The spurs being sometimes very small, the tibiae have to be very 

 closely examined. 



