176 BOMBTLIID^E. 



flattened, thinly haired, but with some 

 strong - bristles towards sides ; 2nd vein 

 generally with a strong loop near tip ; 

 head generally as wide as thorax. (Four 

 posterior cells ; anterior cross-vein often 

 sloping) Lomatiin^;, p. 255. 



The exact limits of the subfamilies is still to some extent a 

 matter of opinion, as is also the location of certain genera. 

 "Williston ignores subfamilies altogether, and Verrall discusses 

 their affinities in some detail.* 



Subfamily ANTHRACIN^E. 



Head broadly rounded or transverse, closely applied to the 

 thorax, even though the occiput be enlarged ; nearly as wide as 

 thorax. Three ocelli. Eyes widely separated in both sexes ; frons 

 often barely narrower in S than $? , and often with an indentation 

 in the middle of the bind margin. Proboscis porrect, short, rather 

 thick; palpi iuconspicuous, labella of moderate size. Antennae 

 widely separated at base, short, never elongate, 3rd joint conical 

 or onion-shaped. 



Thorax barely arched, oblong or nearly quadrate, with rounded 

 corners, moderately or often densely pubescent. No bristles on 

 dorsum, but presutural, supra-alar, and post-alar bristles frequently 

 present, mingled with the pubescence. Scutellum semicircular, 

 usually similarly clothed to the thoracic dorsum, sometimes with 

 conspicuous bristles (Hyperalonia, Exoprosopa); metanotum usually 

 hidden. 



Abdomen a little longer than the thorax, slightly arched, gener- 

 ally approximately oblong, not infrequently obconical, but never 

 tubular or depressed, usually with sparse or dense pubescence like 

 the thorax, often with bands of scales on some of the segments 

 and at the extremity or underside, and frequently with bunches 

 of such scales or thick scale-like hairs at the basal corners. 



Legs moderately long, comparatively slender ; femora often with 

 small spines on lower side ; tibiae nearly always with rows of small 

 spicules and an apical circlet of small spines ; tarsi with the joints 

 more distinctly defined in some genera than others ; pulvilli small 

 or absent; ungues with or without a small tooth at the base. 



Wings with prsefurca long, extending nearly or' quite to anterior 

 cross-vein, the 2nd longitudinal vein originating in a knee-shaped 

 angle, the 3rd vein being in a straight line with the praefurca. 

 Auxiliary vein long ; 1st longitudinal vein long, 2nd vein often 

 forming a loop towards its tip, as does often the upper branch of 

 the always forked 3rd vein. Two, three, or sometimes four 

 (Hyperalonia) submarginal cells ; "f" three or four posterior cells, 



* ' British Flies,' v, p. 478. 



t An additional veinlet adventitiously or specifically sometimes causes five 

 submarginal cells. 



