THE CANADIAN ENTOMOLOGIST 193 



Genus Gnophomyia Osten Sacken. 

 Gnophomyia tristissima cockerelli, new subspecies. 



Female. — Length about 8.5 mm.; wing 7.2 mm. 



Similar to typical tristissima, differing as follows: Antenna? a little longer. 

 Legs somewhat stouter. Wings hyaline, with a few dark seams a^ng the 

 veins, these seams on Rs, i?4+5, M, Cu, Ms and second A; cell Sc dark. Venation: 

 Sc ending beyond the fork of Rs; Sci long, about equal to R2+3. 



Habitat. ^Colorado. 



Holotypc. — 9, Campus of the University of Colorado, Boulder, Colorado, 

 September 20, 1917, (Felicita Claer). 



The distinctl[v bicolorous, longitudinally streaked, wings is the most con- 

 spicuous character to separate this fly from typical tristissima O. S. of the eastern 

 United States, in which the wings are uniformly darkened. The type was 

 kindly sent me by Prof. Cockerell, to whom the form is respectfully dedicated. 

 In the collection of the United States National Museum there are a few speci- 

 mens of this variety, likewise from Colorado (from the collection of C. V. Riley, 

 taken by Morrison). 



Genus Gonomyia Meigex. 

 Gonomyia (Gonomyia) aciculifera, new species. 



Belongs to the noveboracensis group; similar to noveboracensis Alex, but 

 larger; wings with Sc shorter and with Sa at the tip of Sc\; Ra. not so close to 

 Ri at the wing margin; male hypopygium with the ventral pleural appendage 

 expanded at the apex into a paddle-like bmde whose Jower margin is minutely 

 toothed. 



Male. — Length 5 mm.; wing 54 mm. 



Described from an alcoholic specimen. 



Rostrum and palpi entirely dark brown. Antennae dark brown through- 

 out, the basal segments enlarged. Head dark. 



Mesonotum dark, the humeral angles a little brighter. Plieura brownish, 

 brighter posteriorly. Halteres elongated, pale, the k"*Jobs dark. Legs with the 

 coxre dark, the trochanters a little paler; remainder of the legs broken. Wings 

 pale grayish yellow; stigma indistinct; veins l|ight brown. Venation: Sc rather 

 short, ending far before the origin of the sector, the distance between the two 

 only a little less than the length of the basal deflection of Cui; Sci very close to 

 the tip of Sci and about subequal to it; Rs strongly arcuated; Rz+z very long 

 as in this group of species, almost straight be^'ond the origin; R2 semiperpen- 

 dicular, short, the distance on the wing margin between the tips of veins Ri and 

 R2 is a littl/e greater than i?2 alone; cell i?2 a little larger than in noveboracensis; 

 i?4+6 straight, not approaching M1+2 at the wing margin; basal deflection of Cui 

 at the fork oi M. 



Abdomen dark, the posterior margins of the tergites paler. The colours 

 produced by pruinosity in dried specimens are undoubtedly somewhat dif- 

 ferent from those of the alcoholic type just described. Male hypopygium 

 simifer to that of noveboracensis (as figured in the Proceedings of The Academy 

 of Natural Sciences of Philadelphia for 1916, PI. 30, Figs. 79 and 80), but dif- 

 fering in many important respects; the flattened dorsal pleural appendages have 

 but few setcC albng the truncated or concave apex; the long, slender, ventral 

 arm is expanded into a paddte at the tip, this with the lower margin minutelV 



