DASYPOGONIN^ 717 



Antennae with the two basal joints almost equal in length. Face 

 bearing long bristly hairs all over, and the frons bearing long softer 

 hairs. Hind tibiae very clavate. 



PSEUDOHOLOPOGON. 



66 (61) Style thin and pointed, indistinctly jointed. 



Thorax strongly humped anteriorly. Small flics. 



67 (68) Flies clothed with long dense silky or woolly pubescence on the 



face, frons, pleurje, legs, etc., but without any bristles. 



Hind tibias hardly clavate. Metapleural tuft large and dense, and 

 the mesoplcural pubescence extending over the small praealar callus. 

 Alulae not quite absent. 



Eriopogon. 



68 (67) Flies without long or dense pubescence, but with some bristles. 



Hind tibige conspicuously stout and clavate. Metapleural fan 

 composed of long bristly hairs, and the small praealar callus bare. 

 Alulte absent. 



69 (70) Face-beard not dense but extending up to the antennae, very soft- 



haired. 



HOLOPOGON. 



70 (69) Face-beard barely extending up to the middle of the face. 



A pair of ocellar bristles conspicuous. 



Oligopogox, 



The Beitish Genera of Dasypogonince 



are only three in number, and may be easily distinguished as follows : — 



1 (2) Front tibite with a peculiar curved claw at the tip {v. fig. 370). 



Thorax and scutellum without bristles. 



11 Isopogon. 



2 (1) Front tibiae without any peculiar claw at the tip. 



3 (4) Thorax and scutellum with numerous bristles and hairs. 



12 Lasiopogon. 



4 (3) Thorax with only one (rarely 2-3) prsesutural and 2-4 supra-alar 



bristles ; scutellum without any bristles. 13 Dioctria. 



Dioctria is composed of a number (6) of almost bare species, which 

 have the face-beard restricted to the slightly produced neighborhood of the 

 mouth, the frons and ocellar prominence almost bare, the antennse placed 

 on a prominence and with the basal joint long and cylindrical, the thorax 

 with one (rarely two or three) prsesutural and (usually) about four supra-alar 

 bristles but with no bristles on the postalar calli or scutellum, the abdomen 

 almost bare except for a short row of long bristly hindmarginal hairs 

 towards the sides of the basal segment, the hind femora and tibise with a 

 peculiar furry or felt-like pubescence, and the wings with the anal cell open. 



Isopogon has only one British species which is easily known in the 

 male sex by the remarkal)ly long thin basal joint of tiie hind tarsi, and 

 both sexes have the face-beard occupying almost all the arched face, the 

 frons and the ocellar prominence conspicuously hairy, the antennte on no 

 prominence and with the two basal joints equally short and cup-shaped, the 



