80 PKOCEEDINGS OF THE ACADEMY OF [Part I 



out ventrad of the wing-root, passing dorsad of the halteres; the 

 dark brown hne that separates these two pale stripes is about as 

 wide as the narrow dorsal stripe. Halteres light brown, the knobs 

 broken. Legs with the coxae and trochanters yellow; fore femora 

 dark brown; other femora brownish yellow, with a narrow apical or 

 subapical darker brown ring; tibiae and tarsi dark brown. Wings 

 with a faint grayish tinge; stigma indistinctly brownish; veins pale 

 brown, the costal margin whitish; veins comprising the cord darker 

 brown. Venation: Sc short, Sci ending a short distance before 

 the origin of Rs, the distance being about equal to r-m or a little 

 less; Sc2 a short distance from the tip of Sci; Rs short, subangulate 

 at origin; cell 1st Mi open by the atrophy of the outer deflection of 

 Mi; basal deflection of Cui immediately before the fork of M. Ab- 

 dominal tergites dark brown, the sternites more obscure brown. 

 Male hypopygium with the ventral appendage somewhat sword- 

 like in appearance, heavily chitinized, before midlength dilated into 

 a flattened wing; apex of this appendage subcylindrical, the tip 

 suddenly narrowed; dorsal pleural appendage entirely fleshy as in 

 G. helophila, at the base with a small, oval, glabrous lobe; the en- 

 larged apex of the appendage with numerous setae; no intermediate 

 pleural appendage as in G. helophila. 



Habitat. — Peru. 



Holotype, cf , Iquitos, March 5, 1920 (H. S. Parish). 



Gonomyia (Leiponeura) phoroctenia sp. n. Plate IV, fig. 7. 



Rostrum reddish orange; antennae dark brownish black; meso- 

 notum brown, the scutum with the anterior median area yellow; 

 scutellum broadly margined caudally with yellowish; pleura dark, 

 blue-gray pruinose, the dorso-pleural membrane and a broad, longi- 

 tudinal stripe yellowish; halteres with the knobs yellow; wings 

 strongly tinged with brow^n; male hypopygium with a single pleural 

 appendage; penis-guard and gonapophyses complex and asymmet- 

 rical; region of the ninth tergite with two combs of small spines. 



Male. — Length about 4 mm.; wing 3.8 mm. 



Rostrum reddish orange; palpi dark brown. Antennae dark 

 brownish black, the second scapal segment enlarged, suboval; flagel- 

 lum with very long verticils in the male. Head dark, the vertex 

 behind yellowish pollinose. Pronotal scutellum light sulphur yellow. 

 Mesonotal praescutum brown, the lateral margins caudad of the 

 level of the pseudosutural foveae more bluish; scutum dark with a 

 brownish bloom, the anterior median area dull yellow; scutellum 

 broadly dull yellow behind; postnotum light gray pruinose. Pleura 

 with the dorso-pleural membranes dull yellow; remainder of the 

 pleura dark, blue-gray pruinose, with a broad but ill-defined yellow- 

 ish white longitudinal stripe that extends from behind the fore coxae 

 past the root of the halteres to the abdomen. Halteres pale, the 

 knobs yellow. Legs with the coxae blue-gray; trochanters dusky; 

 remainder of the legs dark brown. Wings relatively broad, with a 



