GERON. 279 



Genus GERON, JLj. 



Gero7i, Meigen, Syst. Besch. ii, p. 223 (1820). 



Genotype, Bomhyl'ms Ivjhridus, Mg. (Europe) ; by original 

 designation. 



Head semicircular, narrower than thorax and set low down on 

 it ; epistome short ; mouth-opening large ; proboscis prominent, 

 horny, curved, with narrow labella ; eyes in S contiguous, widely 

 separated in $ . Antenuce porrect, approximate at base, longer 

 than head; 1st joint long, cylindrical ; 2nd very short; 3rd as 

 long as 1st, spindle-shaped. Thorax oval, considerably arched, 

 projecting forward ; thinly pilose or with microscopic tomentum ; 

 scutellum triangular. Abdomen extremely short, conical, tip 

 pointed, thinly pilose. Ze^s slender, minutely pubescent. Winys 

 with 3rd longitudinal vein forked ; anterior cross-vein beyond 

 middle of discalcell, erect : two submarginal cells ; three posterior 

 cells; anal cell nearly reaching border of wing; anal vein attaining 

 the border. 



Rangf. World-wide. 



Lif'e-ldstor>i unknown. 



The two Indian species are thus distinguished : — 



Legs pale brown ; tibiae paler ; length 21-4 mm. argentifrons, Brun. 

 Legs pale tawny ; coxre, tips of femora, and 



hind tarsi black ; length 5 mm albescens, Brun. 



223. Geroii argentifrons, Bmn. 



Geron argentifrons, Brunetti, Rec. Ind. Mas. ii, p. 482 (1009). 



(S . Head with eyes contiguous from the very reduced raised 

 vertex to antennae, facets of moderate and uniform size ; vertex 

 with several long black hairs of variable lengths ; ocelli well 

 separated, pale brown ; frons covered with dull yellowish oblong 

 scales, lying flat on surface, and witii a second clothing of silverj'- 

 white scales ; face bluish white, with silvery reflections seen from 

 above, as are also the lower eye-orbits ; some long black hairs on 

 face ; upper side of mouth-opening yellowish ; occiptit black, 

 with long brownish-grey hairs. Antennse black, tip of 1st and 

 2nd joints sometimes very narrowly whitish, 1st joint about double 

 as long as 2nd ; 3rd distinctly longer than first two together ; 

 basal joints occasionally pale. Thorax black, with long brownish- 

 grey or yellowish-grey pubescence, through which can be seen 

 a lower clothing of very short yellow scale-like hairs ; pleurae 

 bluish grey, with whitish-grey pubescence. Abdomen dorsally like 

 thorax, sides with numerous silvery-white scale-like hairs ; 

 apparently the whole dorsum normally covered with long hairs, 

 which maybe thicker and longer at the sides ; venter like dorsum, 

 except that the long hairs are a little shorter. Legs normally dark 

 brown or blackish ; tibiae always paler, varying in shade from 

 yellowish to moderately dark reddish brown ; femora apparently 



