BRITISH SPECIES OF DIPTEROUS GENUS FANNIA 161 



of moderate length; arista nearly bare; thorax grey-black 

 dusted, with the dorsum indistinctly two-striped; abdomen 

 thickly grey dusted, dorsal line dilated triangularly on each 

 segment, anal organ small ; legs black, base of fore tibia, tip of 

 fore femora anterior surface, and knee-joints yellow ; fore coxae 

 with a thorn on their inner sides; fore tibia with a weaker 

 bristle above the preapical one ; mid coxa armed as in manicata 

 and monilis ; mid femora much dilated, strongest at a little 

 beyond the middle, the bristling much as in the foregoing but 

 rather more conspicuous ; mid tibia of nearly equal thickness 

 to beyond the middle, then on the ventral surface a distinct 

 thickening, produced into a somewhat pointed tubercle, the 

 hind angle very long compared with the fore one ; pubescence 

 on the basal half of the ventral surface very inconspicuous, on 

 the apical side of the tubercle rather longer, and very long at 

 the apex beyond the tubercle; hind femora with a row of 

 very short bristles on their antero-ventral surface, which increase 

 in length as they approach the apex ; hind tibia with a row of 

 about four or five bristles on the antero-ventral surface, a row of 

 rather small even bristles on the basal two-thirds of the antefo- 

 dorsal surface, the usual lower one the strongest, the usual 

 dorsal bristles and two or three weak bristles on the postero- 

 ventral surface; wings nearly clear, third and fourth veins 

 convergent, outer cross-vein bent ; calyptra unequal, yellowish ; 

 halteres yellowish. 

 9 • Very similar to the ? of manicata, but greyer in colour, 

 the most reliable distinguishing point between the two being 

 that in scalaris there is present, as in the <$ , a rather weak 

 bristle on the apical third of the antero-dorsal surface of the 

 fore tibia. The long hair-like bristle at the base of the mid 

 femora, on the ventral surface, is very conspicuous in this 

 species, while in matiicata it is not at all noticeable from the 

 other bristles ; the hind knees are generally distinctly yellow in 

 scalaris, while they are black, or nearly so, in manicata. 



6 to 7 mm. 

 One of the very commonest species. I take it abundantly 

 at Bonhill, and have seen it from various localities. May to 

 October. 



7A. ciliata, Stn., £ . Black ; eyes nearly confluent ; frons slightly, 

 jowls hardly, projecting; antennae of moderate length, third joint 

 about two and a quarter times the second ; arista nearly bare, 

 gradually thickened on the basal third; thorax deep black, 

 hardly shining, slightly grey dusted; abdomen shaped as in 



7 x 



