44 Prof. Charles P. Alexander on 



origin ; r at two-thirds the rather long -R2 + 3 ; i?2 + 3 as long 

 as, or longer than, the petiole of cell 2nd M2, shorter than R2 ; 

 basal deflection of i?4 + 5 arcuated; basal deflection of Cul a 

 short distance before the fork of M. 



Abdominal tergites dark brown ; sternites pale brownish yellow. 

 Male hypopygium with three pleural appendages ; outer appendage 

 a short, flattened, curved blade, the apex produced into a blackened 

 beak; intermediate appendage complex, with a cylindrical base 

 that is dilated into a collar the outer angle of which is produced 

 into a short, black, sjjinous lobe, the proximal angle produced into 

 a straight, slender rod that is approximately as long as the base 

 itself but very slender; irmer pleural appendage very pale, fleshy, 

 suboval, the proximal face with abundant stout setae. Penis- 

 guard consijicuously trifid at apex. Ovipositor with the valves 

 elongate, horn- coloured. 



Hab. South America, without closer determination. 

 Holotype, ,^ (Ex the AVinthem Collection). 

 AUofopot7/pe, $, pinned with the type. 

 Type in the collection of the Vienna Museum. 



Gonomyia (Leiponeura) subfalcifer, sp. n. 



General coloration grey; scapal segments orange; pleura with 

 two silvery white longitudinal stripes ; legs with the femora yellow 

 with a narrow brown subterminal ring ; male hyiDopygium with the 

 outer pleural appendage sickle- shaped and with a single chitinised 

 spine on the proximal face. 



Male. — Length about 3-8 mm. ; wing 4-3 mm. 



Rostrum and palpi dark brown. Antennae with the scaj^al 

 segments obscure orange, the anterior face darker; basal flagellar 

 segments pale, passing into darker brown at the tip of the organ; 

 flagellar segments with long verticils. Head whitish, the centre 

 of the vertex dark brown. 



Pronotum pale, dark brown medially. Mesonotal praescutum 

 brown, the median area slightly darker brown, the lateral margins 

 broadly pruinose ; scutum pruinose, the lobes brown ; scutcllum 

 pruinose, the caudal margin pale; postnotum light grey pruinose. 

 Pleura dark brown, grey pruinose, with two conspicuous silvery 

 white longitudinal stripes, the ventral stripe wider and more clearly 

 defined than the dorsal stripe, the dark stripe between very narrow 

 but distinct; dorso-pleural membrane obscure brownish yellow. 

 Halteres brownish yellow, the knobs broken. Legs with the 

 coxae obscure yellow, dark brown basally; trochanters yellow; 

 only the middle legs remain; femora yellow with a narrow brown 



