20 B. C. ENTOMOLOGICAL SOCIETY 



Tetragoneura marceda sp. nov. 



Male. Length 3.5 m.m. Head black, base of antennae and palpi 

 yellow, remainder of antennae dark brown ; thorax, scutelluni and 

 abdomen brown, hypopygium yellowish ; hairs on thorax and abdomen 

 yellow or reddish brown ; halteres, coxae and femora yellow, tibiae 

 yellowish brown, tarsi dark brown ; wings hyaline, subcostal vein ends 

 in Ri about midway between the humeral cross-vein and base of the 

 radial sector; cul)itus forks close to its base, cuj' detached and attenu- 

 ated at proximal end; cell Rj scarcely as long as wide. 



Twenty-nine males and six females taken at Savary Island and 

 \'ancouver, B. C, April and May. Of these specimens only seven males 

 and two females have the rhomboidal cell complete in both wings ; 

 seven males and one female are zygomorphic, the vein R2-3 being absent 

 in one wing ; fifteen males and three females are destitute of vein R2-3 

 in both wings. In some specimens the cell Ri is very short, vein R2-3 

 almost touching the base of radial sector. 



Female. Like the male, but usually lighter in color, the humeri and 

 genitalia being yellow. 



Tetragoneura fallax sp. nov. 



Male. Length 4.5 m.m. Head black, base of antennae and palpi 

 3ellow ; remainder of antennae dark brown ; thorax and abdomen dark 

 brown; humeri, edge of sclitellum and metanotum yellow; the meta- 

 notum ~inore or less fuscous dorsally ; the large hypopygium mostly 

 dark brown, the interior parts mostly yellow ; legs yellow changing to 

 subfuscous and fuscous in tibiae and tarsi ; setae and hairs yellow ; 

 halteres yellow; wing hyaline, veins strong, subcosta ends in Rj about 

 midway betwen humeral cro§s-vein and base of radial sector; cubitus 

 forks slightly proximad of proximal end of R-M cross-vein, or directly 

 under it; cui not detached; length of cell Rj about 1.5 times its width. 



Female. Color usually more dilute ; genitalia yellow. 



In a series of forty specimens, thirteen males and twenty-seven 

 females, taken at Savary Island and Vancouver in April, May and 

 December, there is considerable variation in : 



(a) Relative position of end of subcost:a. 



(b) Relative position of fork of cubitus. 



(c) Length of small cell. 



Two males and four females have R2-3 wanting in one or both 

 wings. 



Tetragoneura arcuata sp. nov. 



Alale. Length 3 m.m. Head black, base of antennae and palpi 

 3'ellow, remainder of antennae dark brown ; thorax, scutellum, meta- 

 notum and abdomen dark brown, hypopygium largely brown ; hairs on 

 thorax and abdomen yellow ; halteres yellow, the knob tipped with 

 brown ; legs yellow, middle and hind coxae brownish, tibiae and tarsi 



