CHARLES P. ALEXANDER O 



Male. — Length, about 6 mm.; wing, 6 mm. 



Very similar to the female. Antennal segments very broad but scarcely 

 pectinate, each flagellar segment with a distinct but short pedicel. Male 

 hypopygium pale brownish yellow, the dorsal pleural appendage heavily 

 chitinized, black, acutely pointed; gonapophyses similarly chitinized, slightly 

 curved. 



This variety is very close to the typical form and more material 

 of both will be needed to show their true relationship. R. spadici- 

 thorax (Edwards) of the Seychelles Islands also belongs to this 

 group of species, but is abundantly distinct from either of the 

 Eastern forms. 



Genus LIMNOBIA Meigen 



Limnobia subnubeculosa new species 



Antennae black; mesonotum reddish brown with three dark brown stripes, 

 scutellum and postnotum dark; femora with two black bands; wings yellowish 

 gray, clouded with brownish gray; abdominal tergites banded with brown and 

 yellow. 



jT/ait'.— Length, 7.6-7.9 mm.; wing, 9.6-10 mm. 



Female. — Length, 7.4-9 mm.; wing, 8.8-10.4 mm. 



Rostrum and palpi black. Antennae black, the first flagellar segment 

 indistinctly yellowish at base, the flagellar segments with a dense white 

 pubescence. Head dark grayish black. 



Pronotum black. Mesonotum shiny reddish brown, with three dark 

 brown stripes, the median stripe less distinct than the lateral stripes and 

 becoming obliterated some distance before the suture; lateral stripes con- 

 tinued back upon the scutal lobes; a brownish spot is placed on the lateral 

 margin of the praescutum opposite the anterior end of the lateral stripe; 

 scutellum and postnotum dark, shiny. Pleura largely dark brown, a little 

 more yellowish beneath the wing-root. Halteres yellow, the knobs brown, the 

 tips again yellow. Legs with the fore coxae black, the other coxae yellowish; 

 trochanters yellow; femora yellow with two dark brown bands, one apical, 

 the second on the apical third of the segment, the two bands enclosing a 

 subequal yellow band; in some specimens there is a very indistinct third band 

 near mid-length of the femur; tibiae and tarsi brownish yellow, the apical 

 tarsal segments brown. Wings pale yellowish gray, the costal region and 

 the base of the wings more yellowish; brown spots at the tip of Sci and the 

 origin of Rs; extensive brownish gray clouds present on all the veins and 

 covering most of the wing-surface. Venation: r far before the tip of Ri', 

 basal deflection of Cui variable in position, at, slightly beyond or even some 

 distance before the fork of M. 



Abdominal tergites shiny dark brown, the caudal margins of the segments 

 yellowish; sternites dull brownish yellow, the basal portions of the segments 

 darker, the basal sternites clearer yellow. Male hypopygium with a single 

 pleural appendage which is strongly narrowed at the tip; gonapophyses in the 

 form of two, pale, slightly divergent horns. 



TRANS. AM. ENT. SOC, XLVI. 



