86 PROCEEDINGS OF THE ACADEMY OF [Part I 



one is an elongate cylindrical rod that terminates in a curved chitin- 

 ized hook, the inner face before the hook fringed with erect yellow 

 hairs; the intermediate appendage is a little longer, bearing a sharp 

 spine on the inner face beyond midlength, the surface of this append- 

 age with scattered coarse bristles; the proximal appendage is smaller, 

 irregularly bifid, complicated in structure. 



Habitat. — Peru. 



Holotype, cf , Napo River, June 14, 1920 (H. S. Parish). 



Teucholabis jocosa Alexander. 



1913. Teucholabis jocosa Alexander, Ent. News, vol. 24, pp. 440, 441. 



Teffe, Brazil, December 27, 1919 (H. S. Parish). 

 Yurimaguas, Peru, March 28, 1920 (H. S. Parish). 

 Napo River, Peru, June 15, 1920 (H. S. Parish). 



Teucholabis omissinervis sp. n. 



General coloration yellow, the anterior median area of the meso- 

 notal praescutum slightly darkened; legs yellow, only the terminal 

 tarsal segments darkened; wings yellow, unmarked; cell 1st Mi 

 open by the atrophy of the outer deflection of Ms. 



Male. — Wing 4.4 mm. 

 Female. — Wing about 4.2 mm. 



Head lacking. Pronotum yellow. Mesonotum clear reddish yel- 

 low, the anterior median area of the praescutum in some specimens 

 a little darkened. Pleura whitish yellow, a little darker dorsally 

 to produce an indistinct longitudinal stripe. Halteres pale, the 

 knobs a little darker. Legs yellow, the terminal tarsal segments 

 infuscated. Wings with a yellowish tinge, more saturated in the 

 costal region; stigma rather indistinct, yellowish; veins yellow. 

 Membrane with the microtrichiae larger than usual in the genus. 

 Venation: Sc of moderate length, 5c i ending just before midlength 

 of Rs; Rs long, gently arcuated; r on R^+s less than its length beyond 

 the fork of Rs; cell 1st Mi open by the atrophy of the outer deflec- 

 tion of Mz; petiole of cell 2nd Mi about equal to the cell; basal de- 

 flection of Cui at or a short distance beyond the fork of M. Abdo- 

 men brownish yelloAv. Male hypopygium with the pleural append- 

 ages moderately complicated, a long, digitiform hairy lobe and 

 two chitinized blades, the outer of which is acicular, the inner one 

 flattened, shaped somewhat like a pruning knife, the apex black- 

 ened. 



Habitat. — Peru. 



Holotype, cf, Yurimaguas, April 7, 1920 (H. S. Parish). 

 Allotopotype, 9 , April 7, 1920. 

 Paratopotypes, 3 9 's, April 7-10, 1920. 



Teucholabis omissinervis is readily told from all described species 

 of the genus by the open cell 1st Mi. 



