I 



THE DIPTEROUS GENUS DOLICHOPUS IN NORTH AMERICA. 63 



Ty'pe locality. — District of Columbia and Illinois. Melander and 

 Brues report it from Wisconsin. Insects of New Jersey from West- 

 ville, May 19, and Clementon, May 30. 



No. 25. DOLICHOPUS BEATUS, new species. 



Male. — Length 4.5 mm.; of wing the same. Face wide, silvery 

 white. Front dark green, shining. Antennae black; third joint a 

 little longer than wide, somewhat pointed at tip. Orbital cilia 

 wholly black. 



Thorax dark green, shining, but with traces of brown pollen on the 

 front of the dorsum, which is visible only when viewed in certain 

 directions; pleurae dulled with gray pollen. Abdomen dark green 

 with coppery reflections on fourth and fifth segments and black 

 incisures; there are only faint traces of white pollen on the lower 

 part of the sides. Hypopygium (fig. 25) small, about the size of the 

 fifth abdominal segment,' black; its lamellae small, black, somewhat 

 crescent shaped, their convex edge fringed with delicate hairs. 



Coxae and femora black, their extreme tips yellow. Middle and 

 hind femora each with two preapical bristles, placed one below the 

 other, the lower one being a little nearer the base of the femora than 

 the upper one. Fore tibiae and basal half of first tarsal joint yellow. 

 Fore tarsi but little longer than their tibiae, infuscated from near 

 the middle of the first joint (middle and hind tibiae missing). Calyp- 

 ters and halteres yellow, the former with black cilia. 



Wings grajdsh, almost imperceptibly tinged with brown along the 

 front; costa scarcely enlarged at tip of first vein; last section of fourth 

 vein a little bent just beyond its basal third; hind margin of wing a 

 little indented at tip of fifth vein; anal angle of wing rounded; tips of 

 third and fourth veins not very close together. 



Female. — Length 5 mm. Face gray, very wide; third antennal 

 joint about as in the male only a little shorter; front dark green, some- 

 times with violet reflections at the vertex. Abdomen dark, almost 

 blackish green; legs and feet black; anterior tibiae and basal half, 

 sometimes the whole, of middle tibiae yellowish; front tarsi only a 

 little paler at base; middle and hind femora each with two preapical 

 bristles; wings as in the male. Middle tibiae with two bristles below; 

 their basitarsi without a bristle above. 



Described from 1 male and six females taken on Craig's Mountain, 

 Idaho, by J. M. Aldrich. 



T^pe.— Male, Cat. No. 22988, U.S.N.M. 



No. 26. DOLICHOPUS DEMISSUS, new species. 



i/aZe.— Length 4 mm.; of wing 3.5 mm. Face rather narrow, its 

 pollen yellow. Front green. Antennae (fig. 26a) wholly black; 

 third joint but little longer than wide, rounded at tip. Orbital cilia 

 wholly black. 



