74 ENTOMOLOGICAL NEWS [March, '20 



Psaronius brevitibia sp. n. 



General coloration light brown; head and mesonotal praescutum un- 

 marked with darker; metatarsi whitish; tibiae short; wings pale yellow, 

 sparsely marked with darker; vein R2 entirely atrophied. 



9. — Length 24 mm.; wing 14.4 mm.; abdomen alone 19.5 mm. Ros- 

 trum and palpi dark brown. Antennae with the scapal segments light 

 brownish yellow; flagellum broken. Head rufous brown, narrowly silvery 

 adjoining the eyes; occiput and adjoining parts of the vertex dull brown. 



Mesonotal praescutum light brown without distinct stripes; scutum 

 and postnotum with a very indistinct median line. Pleura pale without 

 distinct markings. 



Legs with the femora and tibiae light brown, the tips of the latter nar- 

 rowly dark brownish black; metatarsi whitish, the base and apex narrowly 

 darkened; remainder of the tarsi dark brown; tibiae comparatively short 

 (hind tibiae 1 1.5 mm.; in P. pygmaeiis 14.2 mm.). 



Wings pale yellow, the costal and subcostal cells deeper yellow; small 

 dark brown seams at the origin and fork of Rs, and as very narrow seams 

 along the cord and outer end of cell ist Mr, wing-apex in cells R2, R3, Ri 

 and Ml faintly darkened; veins dark brown, C, Sc, R, Rs and Rz yellow. 

 Venation: vein R2 entirely atrophied, quite as in P. abnormis Alexander; 

 cell Ml about equal to or a little shorter than its petiole. 



Abdominal tergites brown, the sternites more yellowish. 



Holotype: 9 , Obidos, August 28, 1919 (H. S. Parish). 



By means of the author's key to Psaronius, cited under the 

 preceding species, P. brevitibia would run to P. abnormis, of 

 Paraguay, a greyish fly with the costal margin of the wings 

 conspicuously infuscated. It much more resembles P. pyg- 

 maeus Alexander (Guiana-Brazil) which has vein R2 imper- 

 fectly preserved, being represented by a short spur that is 

 fused with Ri at the tip; this species has the tibiae consider- 

 ably longer as given above, and the details of venation and 

 coloration are slightly different. 



Polymera conjunctoides sp. n. 



General coloration light brown; thoracic pleura with a narrow, black, 

 longitudinal stripe; wings grey; cell Mi deep; ovipositor with the valves 

 long and straight. 



9.^ — Length about 3.5 mm.; wing 3.8 mm. Rostrum and palpi dark 

 brown; flagellar segments in the female long-oval. Head brown. 



Pronotum testaceous. Mesonotum light brown. Pleura pale brownish 

 testaceous with a narrow black longitudinal stripe continued from the head 

 to the base of the abdomen, passing just beneath the halteres. 



