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front and upper parts and the amount of this enlarging specifically 

 varying in a certain extent. 



Thorax thick and short, quadrate with rounded angles ; humeri 

 distinct and round, clothed with a dense tomentuni which is usually 

 paler than that on the disc of the thorax ; praealar calli large and 

 roundish though its inner end almost always pointed, and often rather 

 differently coloured from the disc of the thorax ; postalar calli obliquely 

 transverse between the base of the wing and the scutellum. Pubescence 

 on the disc rather inconspicuous and usually composed of two distinct 

 kinds of hairs, of which one kind stands erect over most of the disc 

 and scutellum but does not exist on the front part of the disc, while 

 the other kind is pale and lies more depressed all over the disc and 

 at least round about the margin of the scutellum and is much thinner 

 and more liable to be rubbed or worn away than the erect hairs ; in 

 addition to these there are patches of depressed pale hairs above the 

 wing-bases and against the postalar calli ; pleurae with longer shaggier 

 pubescence especially on the upper part. 



Wings usually hyaline though more or less infumated, rarely 

 spotted or marked in any way, and with scarcely any deviation from 

 the typical form of the Tabanidae, except that the upper branch of 

 the cubital fork has sometimes a recurrent veinlet near its base as in 

 many Chrysops and Haematopota ; posterior cells normally open, but 

 the first one narrowed or even occasionally closed ; anal cell closed ; 

 wing-membrane rippled all over, practically glabrous. Alulae strongly 

 developed, and so large that when the wings are at rest they are 

 pushed upright against the sides of the scutellum. Squamae very well 

 developed, and with darker margins which bear a very short fringe 

 except on the alar pair near the angle where there is a conspicuous 

 tuft of long hairs ; thoracal pair largest but outspread or elevated and 

 not concealing the halteres. Halteres moderate. 



Legs simple, but with two almost always unequal apical spurs 

 on the middle tibiae ; front coxae long, being fully two-thirds as long 



