November, 1910.] 245 



in preceding species, antennae black and rather small, palpi pale yellow ; 

 wings yellowish-brown, costa more than f wing length, fringe very long, 

 1 about i longer than 2 + 3, angle at fork moderate, 1st thin vein gently 

 curved at its origin ; legs yellow, hind femora darkened at tip, tibial cilia 

 very iine and indistinct ; hypopygiiun white with only the hind margin 

 narrowly black, pubescence black, ventral plate large and white, anal organ 

 black and of moderate size l-^li mm. alhicaudata, n. sp. 



57 (56) Hypopygium Mack. Under pair of supra-antennal bristles minute. 



58 (59) The marginal hairs 07i 6th ahclominal segment very large and 



conspicuous. 

 $ . Thorax and abdomen black ; frons barely \ broader than long, black, upper 

 pair of supra-antennal bristles large and approximate, under pair minute, 

 antennae rather small and brown, palpi pale yellow ; wings and veins pale 

 yellowish-brown, costa more than f but considerably less than | wing 

 length, 1 hardly longer than 2 + 3, angle at fork largish, 1st thin vein 

 gently but distinctly curved at its origin from the fork ; legs yellow, hind 

 femora, not darkened at the tip, their under-side with some moderately long 

 and loose hairs on the basal half, tibial cilia rather small and numerous 

 but distinct ; the conspiciious hairs on the last abdominal segment (nearly 

 as long as the segment itself) are 6 or 8 in number and disposed at regular 

 intervals round the margin on its dorsal aspect, whilst irregularly grouped 

 ai-e 2 or 3 smaller ones at the edge of the venter on each side ; hypopy- 

 gium of moderate size, without bristles, ventral plate dusky, short and 

 broad, anal organ papilla-like, yellow or dusky yellow... 



1^- mm. spinicincta, n. sp. 



59 (58) Without such hairs. 



S ? . Thorax and abdomen black, the former occasionally with an obscure 

 reddish tinge ; frons and its' bristles as in spinicincta, antennae rather small, 

 black or sometimes brown, palpi yellow ; wings as in spinicincta, but rather 

 darker with the veins browner and costa not more than ^ wing length ; 

 legs pale yellowish-brown, hind femora armed underneath as in spinicincta, 

 tibial cilia larger and less nvxmerous than in that species ; hyijopygium of 

 moderate size, without bristles, ventral plate yellow and flap-like, reaching 

 to middle of imder-side, anal organ yellow and of ordinary jDroportions... 



1\ mm. sylvatica, n. sp. 



60 (53) Halteres black. Meso'pleurx bristly, or (hirticaudata) bare, 



61 (62) Mesopleurse bare. 



S . Thorax and abdomen black ; frons about | broader than long, hardly 

 shining, upper supra-antennal bristles large and approximate, under ones 

 minute, antennae rather small, palpi brown ; wings pale grey, costa fully 

 f wing length, 1 longer but not greatly longer than 2 + 3, angle at fork 

 moderate, 1st thin vein without appreciable curve at its origin; leo-s 

 brownish-black, tibial cilia fine and delicate, fore tarsi slender ; abdomen 

 fringed as in involuta with strong bristly hairs on the last segment or two 

 just above the venter, increasing in size from before backwards and con- 

 tinued in unreduced form on to the hypopygimu, giving the latter a rough 



V 



