snow: DIPTERA of COLORADO AND NEW MEXICO. 233 



Syrphus disgregus, n. sp. 



Male, female. Eyes pilose. Antennje black. Face greenish yel- 

 low with black stripe. Three bands of abdomen interrupted. — Length 

 6 — 8 mm. 



Male. Head black. Vertical triangle with light colored, and 

 frontal triangle with black, pile; the latter yellovvish gray pollinose, 

 except on the middle and anteriorly. Antennae black or fuscous 

 black. Face of a bright greenish yellow, with a narrow median black 

 stripe which does not reach the antennae, and sparse black pile on the 

 sides; tubercle large; oral margin bordered with black; cheeks 

 broadly black. Eyes pilose. Occiput grayish pollinose and with 

 yellowish gray pile. Thorax shining metallic greenish black, covered 

 with long, altogether light colored pile. Scutellum bright yellowish 

 brown with scarcely any opalescent reflections; pile long, black dis- 

 tally, and light colored on basal half. Abdomen black, a little 

 shining, with greenish yellow spots which in drying may become more 

 yellowish or brownish, especially on the distal segments; spots of 

 first segment round, sometimes a little oval, separated from the lateral 

 margins; second and third segments each with a pair of sublunate 

 spots which reach the lateral and sometimes the anterior margins; 

 the inner ends of these spots are enlarged and round, the outer ends 

 scarcely at all enlarged, and square; the emargination of the spots is 

 not very deep; fourth and fifth segments with narrow greenish yellow 

 posterior bands, the latter with spots of the same color in the anter- 

 ior corners. Pile of abdomen black except on the basal and yellow 

 portions; hypopygium metallic black, slightly greenish. Halteres with 

 a greenish yellow knob. Legs brownish, anterior femora black on 

 their proximal half; hind femora black, except the tip; distal half of 

 hind femora, the hind tarsi, and the three middle joints of the anter- 

 ior tarsi, fuscous brown; anterior tibice occasionally partly brown 

 near their middle. Wings almost hyaline, sometimes slightly tinged 

 with brown; stigma brown. 



Female. Front black, upper third and vertex bronze black, very 

 shining; across the middle with a broad fulvous narrowly interrupted 

 pollinose band which extends along the sides as far as the antennae, 

 leaving just above the latter a shining black area; sparse pile of front 

 black. Abdomen more broadly oval than in the male; the lunate 

 spots on the second and third segments reach the anterior margin, 

 which in the male they rarely do except sometimes those of the fourth 

 segment; sixth segment with a greenish yellow hind border. Legs 

 slightly lighter than those of the male. Wings of a brownish tinge. 



Twenty-three males and thirty females. Hop Canyon, Magdalena 

 mountains, N. M., (July to Aug., 7500 — 8500 ft., on flovyers of a, 

 species of Geraniuni). 



