eg [jrarch, 



stripe ; frons, epistome, and jowls very narrowly projecting ; antenna; of 

 modci'ate length, 3rd joint two and a qiiarter times as long as the 2nd, arista 

 pubescent, thickened at the base ; palpi normal ; thorax dull black, sides and 

 front undusted, distinctly grey dusted behind ; abdomen dull black, base of 

 segments laterally grey dusted, dorsal stripe much dilated at apices of seg- 

 ments, and hardly separable from the lateral black marks nearer the base, in 

 some positions the segments seem to be only narrowly diisted at the base 

 laterally ; anal organ not very prominent (in the single specimen before me, 

 with two small backward directed appendages, prodiiced into sharp points at 

 their apices) ; legs black, fore knees only inconspicuoiisly paler ; fore femora 

 and tibia with only the normal bristling ; mid femora not greatly thickened, 

 constricted at the apex, with an antero-ventral row of long bristles, beginning 

 at near the base, decreasing in length, but becoming closer placed till about 

 two-fifths from the apex, from where they form a comb-like row on the con- 

 stricted portion ; a somewhat similar row of longer, but rather weaker, bristles 

 on the postei'O-ventral surface ; ventral bristle long and strong ; postero-dorsal 

 surface with long, soft, curved, hair-like bristles ; mid tibia with the apical 

 two-fifths distinctly, but not greatly thickened, much as in verrallii, Stn., but 

 longer, the pubescence on the ventral siirface very short and sparse on the 

 basal unthickened portion, but longer and erect on the apical two-fifths ; a 

 rather weak bristle on each of the antero-dorsal and postero-dorsal surfaces in 

 addition to the iisvial stronger lower one ; hind femora bent, and dilated, 

 thickest at about one-third from the apex, antero-ventral surface with a row of 

 hair-like bristles, which inci ease greatly in length from the base to the thickest 

 part of the femoi-a, and then decrease to the apex, a row of about six long, 

 liair-like bristles on the basal two-fifths, and a group of about nine very long, 

 hairlike bristles on the thickened portion beyond the middle of the postcro- 

 ventral surface, a few very short hairs on the tip fifth ; hind tibia with the 

 usual dorsal bx'istles, two antex'O- ventral bristles, and (in the single specimen) 

 no antero-dorsal bristle ; calyptra blackened, unequal in size ; halteres yellow ; 

 wings darkened along the front half, clearer behind, 3rd and 4th veins nearly 

 l^arallel, outer cross vein nearly straight, last portion of the 4tli vein nearly 

 three times the length of penultimate. 4 mm. 



The single (^ of this very distinct species was taken by Mr. A. 

 E. J. Carter at Aberfoyle, June 30th, 1904. It is quite distinct from 

 any other British species, and cannot even be confounded with any 

 European species. 'Bothfasciculata, Lw., and hirticeps, Stn., have the 

 hind femora as in this species, but the former has the base of the 

 abdomen yellow, and the latter has the eyes densely haiiy. Afra, 

 Stn., differs also in many particulars from this species in the arrange- 

 ment of the bristles according to Stein's description, and in the absence 

 of the thickening of the femora. 



Bonhill, Dvunbartonshire : 

 December, 1909. 



