244 BRITISH GUIANA TIPULIDAE 



short, stout and cylindrical, sparsely clothed with long hairs; ventral ap- 

 pendage a long chitinized sickle-shaped arm which is directed ventrad and 

 then caudad and mesad, at the tip directed outwards; gonapophyses mod- 

 erately prominent, the penis-guard not conspicuous. 



Holotype.cf, Bartica, December 23, 1912. 

 Paratype,cf , topotypic, December 23, 1912. 

 Gonomyia (Leiponeura) puer Alexander 



1912. Gonomyia {Leiponeura) -puer Alexander, Proc. U. S. Nat. Mus., 

 xliv,506, pl.66, ng.14. 



Bartica, ten cf, 9, January 3, 1913 to January 10, 1913. 



Genus ERIOPTERA Meigcn 

 1803. Erioptera Meigen, lUiger's Magazine, ii, 262. 



Subgenus MESOCYPHONA Osten Sacken 

 1809. Mexocyphona Osten Sacken, Monograph Dipt. N. Am., iv, 152. 



Erioptera (Mesocyphona) parva Osten Sacken 



1859. Erioptera parm Osten Sacken, Proc. Acad. Nat. Sci. Phila., 1859, 

 227. 



Twenty-one, cf, 9, Bartica, December 10, 1912 to February 8, 

 1913. 

 Erioptera (Mesocyphona) immaculata Alexander 



1913. Erioptera {Maocyphona) immaculala Alexander, Proc. U. S. Nat. 

 Mus., xliv, 518, 519, pi. 66, fig. 20. 



One 9 , Bartica, January 28, 1913. 

 Erioptera (Mesocyphona) bicinctipes Alexander 



1913. Erioptera (Mesocyphona) hicinclipe-^ Alexander, Proc. U. S. Nat. 

 Mus., xliv, 519. 



Three 9 , Mallali, March 11, 1913 to April 5, 1913. 



Genus GNOPHOMYIA Osten Sacken 

 1859. Gnophomyia Osten Sacken, Proc. Acad. Nat. Sci. Phila., 1850, p. 223. 

 Gnophomyia arcuata sp. n. 



Grayish black without yellow markings; halteres dark throughout; 

 wings with the membrane hyaline, cell Ri very broad at the tip, veins fti 

 and R, being divergent apically. 



Female. — length 6 mm. ; wings, 5.4 mm. 



Female. — Rostrum and palpi dark brownish black. .Antennae brownish 

 black. Head brownish black. 



Thorax rather uniformly dark grayish black without yellow markings. 

 Halteres dark throughout. Legs dark brown. Wings hyaline, the stigmai 

 spot quite indistinct, pale brown; veins dark brown. Venation; (see pi. 

 IV, fig. 6) basal deflection of flj+, very arcuated, sub-perpendicular, the cross- 



