60 Journal New York Entomological Society. [Vol. xiii 



Dorsum of thorax marked with a pair of whitish pruinose vittte on slightly more 

 than its anterior half, the sides, front angles and greater part of pleura thinly 

 grayish pruinose. Black, bases of the joints of the tarsi yellowish. Abdomen 

 somewhat polished. Femora rather slender, not spined. Wings hyaline, 

 slightly tinged with yellowish in the marginal cell ; third vein reaches three 

 fourths length of wing, apex of first vein slightly before middle of the third, 

 fourth vein forks nearly at the small crossvein. Length 2 mm bivittatus.* 



5. Abdomen on basal half yellow, legs chiefly yellow. Black, the halteres, basal 



half of abdomen, genitalia and legs except knees, apices of tibia; and whole of 

 last tarsal joint, yellow, a brownish band near middle of hind tibia". Mesono- 

 tum highly polished. Femora slender, without spines. Wings hyaline, third 

 vein nearly reaches three fourths length of wing, apex of first vein near middle 

 of the third, fourth vein forks slightly before the small crossvein. Length 



2 mm flavoniger.^ 



Abdomen wholly black, legs chiefly black. Black, the basal half of the 

 antennae, the palpi, stems of halteres, a band before apex of each front femur, 

 one near apex of first two pairs of tibia', and the tarsi, yellow. Body highly 

 polished, thorax gibbous. Femora not spined, rather slender, the hind ones 

 elongated and thickened toward the apices. Wings hyaline, venation as in 

 flavoniger except that the apex of first vein is noticeably before middle of the 

 third. Length 1.25 mm gibber. % 



6. Wings hairy, at least toward the apices 14 



Wi ngs bare 7 



7. With at most a small brown spot on either wing, situated on the small crossvein.. 9 

 With distinct brown markings on the wings 8 



8. Yellow, a pair of widely separated vittse on the mesonotum, a streak beneath 



each wing, the front, lateral and hind margins of the abdominal segments 

 beyond the second, the knobs of the halteres, apices of hind femora and of 

 their tibia;, also the last joint of their tarsi, black. Antenna 3 nearly as long as 

 the body, the latter highly polished. Femora rather slender, not spined, first 

 joint of tarsi longer than the following three together, the third slightly 

 shorter than the fourth, the latter less than half as long as the fifth, which 

 bears a pair of stout blunt spines near the base, one of the claws of each tarsus 

 is more than twice as long as the other, the former being unusually long. 

 Wings hyaline, a small brown spot extends from apex of first vein over the 

 small crossvein, a second somewhat larger brown spot reaches from apex of 

 third vein over halfway across the first posterior cell ; third vein reaches three 

 fourths length of wing, apex of first vein near one fifth length of the third, 

 fourth vein forks far beyond the crossvein. Length 2 mm pictus.\ 



* Eureka, Cal. Four females collected May 24 and June 6 by Mr. H. S. Bar- 

 ber. Type No. 8353, U. S. National Museum. 



f Bear Lake, British Columbia. Two males collected. July 20 by Mr. R. P. 

 Currie. Type No. 8354, U. S. National Museum. 



1 ayamas, Cuba. A female specimen collected January 16 by Mr. E. A. 

 Schwarz. Type No. 8355, U. S. National Museum. 



§ Virginia. A female specimen collected June 16, by Mr. Theo. Pergande. 

 Type No. 8356, U. S. National Museum. 



