\\xii. '21 | ENTOMOLOGICAL NEWS 293 



$. Length about 2.5 mm.: wing 3.5 mm. Rostrum and palpi dark 

 brown. Antennae of the male unusually elongate for a member of this 

 genus; if bent backward extending practically to the end of the bod\ ; 

 scapal segments brown; flagellum black, the segments with erect white 

 hairs. Head dark gray. 



Mesonotal praescutum brownish medially, the margin broadly obscure 

 yellowish ; remainder of the mesonotum brown. Pleura brownish tes- 

 taceous. Halteres pale, the knobs brown. Legs with the coxae and 

 trochanters pale testaceous ; femora and tibiae obscure brownish yellow, 

 the tips broadly dark brown ; tarsi dark brown. Wings showing the 

 first evidences of atrophy, narrowed, especially on the basal half; mem- 

 brane grayish stibhyaline, the veins brown with long dark hairs. 



Abdomen dark brown, the hypopygium brighter. Male hypopygium 

 with the apparent pleural appendage appearing as a stylet-like black 

 spine, straight and slender, tapering to the acute tips, which are decussate 

 across the genital chamber. 



Holot\pe: ? . Ampaiansjo. Catamarca, altitude 2,300 meters, 

 December 1, 1920 (V. \Y iser). 



Rhabdomastix (Sacandaga) basalis sp. n. 



General coloration black; halteres yellow; wings blackish, the basal 

 fourth yellowish; Sc not extending far beyond the origin of Rs; r 

 present. 



$ . Length 2.8-3 mm. ; wing 3 mm. $ . Length 3.2 mm. ; wing 3.4 

 mm. Rostrum and palpi black. Antennae short in both sexes, the scapal 

 segments black; flagellum brownish yellow to yellowish brown; verti- 

 cils elongate. Head black. 



Mesonotum dark brownish black, praescutum dusted with brown, the 

 extreme lateral margins very narrowly and indistinctly yellowish. Hal- 

 teres yellow. Legs with the coxae dark brown ; trochanters obscure yel- 

 low; femora dark brown, more yellowish basally; tibiae and metatarsi 

 obscure yellow, tipped with brown; remaining tarsal segments brown. 

 Wings strongly in fumed with blackish; about the basal one-fourth con- 

 spicuously yellowish, this coloration including practically all of the sec- 

 ond anal cell ; veins dark brown, yellowish in the basal portion of the 

 wing. Venation : Sc rather short, Sc\ ending a short distance beyond 

 the origin of A'v. Sc2 not far from the tip of Sc 1 ; Rs long; r present, 

 inserted on A'2+3 about half its length beyond the fork of Rs; cell R- 

 large, vein R2 straight; cell 1st KI2 closed, or, in rare instances, open 

 by the atrophy of in ; basal deflection of Cu\ immediately beyond the 

 fork of .17. Anal angle of wing prominent. 



Abdomen black, sparsely dusted with a brown pollen. Male hypo 

 pygium relatively large and with stout pleural appendages. In the fe- 

 male the antennae are darker ; head and thorax more pruinose ; mesono- 



