200 JotJRNAL New York Entomological Society. [Vol. xxi. 



Rostrum and palpi dark brownish black ; antennae dark brownish black, 

 scapal and four basal segments of the flagellum enlarged, oval, the remaining 

 flagellar segments abruptly becoming elongate-oval ; head dark brownish gray. 



Mesothoracic dorsum dark clove brown without distinct darker stripes, 

 lateral margin of the sclerite narrowly bright yellow, extending from one wing- 

 base to the other, broadest in front ; scutum dark brown ; scutellum dull yellow, 

 postnotum brown. Pleura dark brownish gray, with a broad oblique band, 

 yellowish in some lights, whitish in others, extending from above and behind 

 the posterior coxae towards the cervical sclerites, ending on the mesopleura. 

 Halteres pale, knob brown. Legs, coxae light brown, darker basally, remainder 

 of the leg dark brown. Wings suffused with darker, veins dark brown. Vena- 

 tion (see PI. 2, fig. 6) : Sc long, ending rather far beyond the origin of Rs, 

 fork of i?^3 long, about as long as its petiole, veins issuing from cell ist M, 

 long, basal deflection of Cm, before the middle of cell isl M,. 



Abdomen dark grayish brown. Male hypopygium (see PI. 3, fig- 3) with 

 the gth tergite produced into a prominent median lobe which is deeply notched. 

 Pleural pieces elongate-cylindrical, the dorsal inner angle produced entad into 

 a short subchitinized arm; from the end of the pleura is a strong, curved, 

 chitinized hook, directed entad and cephalad, a few short hairs at intervals 

 along this hook; behind the chitinized hook is a straight fleshy appendage 

 directed caudad ; gonapophyses long, straight, directed caudad, at the tip some- 

 what twisted and strongly chitinized, before the tip on the inner face, with a 

 strong curved spine ; guard of the penis long and slender, scarcely enlarged at 

 the tip, which is truncated. 



Holotype, c?, Valle de las Papas, March 29, 1912. 



x\llotype, ?, with the type. 



Paratypes, 13 males, 4 females, with the type. 



Genus ERIOPTERA Meigen. 

 Subgenus MESOCYPHONA Osten Sacken. 



9. Erioptera (Mesocyphona) sp. 



Two specimens, <?, ?, from the Valle de las Papas, March 29, 1912, 

 not in proper condition to determine more accurately. 



Subgenus ERIOPTERA Meigen. 



1 0. Erioptera (Erioptera) andina new species. 



Brown, the pronotal scutellum light yellow, legs brown, wings suffused 

 with brown, halteres brown at the tip, the stem pale. 

 Male, length, about 4 mm. ; wing, 6 mm. 

 Female, length, 4.7 mm.; wing, 6.3 mm. 



