2l8 ENTOMOLOGICAL NEWS XXXI, *2O] 



pleura yellow with two brown longitudinal stripes; halteres brown, the 

 knobs yellow; legs brown; wings yellowish gray, the stigma indistinct; 

 male hypopygium with the outer pleural appendage a chitinized hook 

 with a short horn near its base. 



cf. Length about 4 mm.; wing 3.8 mm. 



Rostrum brown; palpi dark brown. Antennae of the male provided 

 with very long verticils as usual in this group of species; first scapal seg- 

 ment yellow; second scapal segment enlarged, dark brown, margined with 

 yellow; remainder of the antenna dark brown. Head light yellow with 

 a large brown blotch on the vertex. 



Pronotum whitish yellow. Mesonotal praescutum with three dark 

 brown stripes that are sparsely purplish gray pruinose, entirely confluent 

 in front, separated behind to show the yellow ground-color; lateral mar- 

 gins of the praescutum broadly yellow; scutum yellow, the center of each 

 lobe purplish brown, this color produced by the backward extension of 

 the lateral praescutal stripes; scutellum yellow, with a conspicuous brown 

 median blotch at the base; postnotum brownish. Pleura yellow with 

 two conspicuous brown longitudinal stripes, the more ventral suffusing 

 the sterno-pleurites; mid-line of the sternum yellow. Halteres pale 

 brown, the base of the stem and the base of the knobs darker; remainder 

 of the knobs conspicuously light yellow. 



Legs with the coxae and trochanters pale; remainder of the legs pale 

 brown, the distal tarsal segments darker. 



Wings with a strong yellowish gray tinge; stigma barely indicated by 

 a long, dusky suffusion in cell Ri; veins pale. Venation: Sc rather 

 short, Sci ending a short distance before the origin of Rs; Sc2 removed 

 from the tip of Sci to a distance that is but little shorter than r m; Rs 

 rather short, almost square at origin; cell ist M.2 broad, the basal deflec- 

 tion of Cui at or immediately before its fork. 



Abdominal tergites dull yellow, with a broad, brownish median stripe; 

 sternites yellow. Male hypopygium with the pleurites moderately 

 stout, the outer angle produced into a long, stout, fleshy lobe; outer 

 pleural appendage a long, chitinized hook that is broad at the base, nar- 

 rowed gradually to the sinuous, acute tip, beyond the base with a short, 

 stout horn; inner pleural appendage very small, fleshy, provided with 

 stout bristles and tipped with a powerful spine. Penis-guard formed as 

 two parallel flattened blades, the tips blackened and produced into a 

 short beak that is directed cephalad; gonapophyses black, bent slightly 

 at their tips which are minutely and irregularly toothed. 



Habitat: Argentina. 



Holotype, cf, Province of Buenos Aires, October u, 1919, 

 (('. Bruch). i cf, 2 9 , La Aranja, Alta Gracia, Prov. de 

 (Yirdoba, April 1-8, 1920 (C. Bruch). 



