THE DIPTEROUS GENUS DOLICHOPUS IN NORTH AMERICA. 87 



their tibiae, first joint as long as the three succeeding joints 

 taken together; fourth and fifth joints of about equal length; third 

 a little longer than the fourth, yellow, a little darker from the tip 

 of the first joint. Middle tarsi equal to their tibiae in length, black 

 from the tip of first joint. Hind tarsi one and a fourth times 

 as long as their tibiae, black. Calypters and halteres yellow, the 

 former with dehcate black cilia; these cilia appear whitish in 

 certain lights and there are always some of the hairs that are pale 

 yellow or white. 



Wings (fig. 46) a little grayish; costa not enlarged at tip of first 

 vein; last section of fourth vein bent beyond its basal third; hind 

 margin of wing not indented at tip of fifth vein, evenly rounded, the 

 anal angle being nearly obsolete, 



Fev^ale,— Face as wide as the front, but still not very wide for a 

 female; silvery white; hind femora not ciliated, but with a row of 

 very delicate little hairs on lower inner edge; anal angle of wing 

 slightly more prominent than in the male. Otherwise about as in 

 the male. Middle tibiae with one not very large bristle below, their 

 basitarsi without a bristle above. 



Described from 8 males and 7 females from Opelousas, Louisiana, 

 March, April, and May (Pilate, collector), and Lafayette, Indiana, 

 May 16, June 5, and Oct. 6 (all from the collection of J. M. Aldrich); 

 1 male and 2 females from Shdell, Louisiana, July 2-6 (J. S. Hine). 



Type.—Uale, Cat, No. 23000, U.S.N.M., from Lafayette, Indiana. 



No. 47, DOLICHOPUS PARTITUS Melander and Brues. 



Dolidiopus partitus MeijA.^jdbr and Brues, Biol. Bull., vol. 1, 1900, p. 135, fig. 



Male. — Length 5-5,5 mm,; of wing the same. Face wide, a little 

 less than half as wide as long, yellowish brown, paler below the trans- 

 verse ridge, at each end of which is a white dot. Front violet, more 

 green around the edges. Antennae (fig, 47o) wholly black; third 

 joint a little longer than wide, oval. Orbital cilia wholly black; 

 however, there are always a few yellowish bristles near the proboscis 

 and in one specimen seven of the lower cilia are also yellowish. 



Thorax dark green or brownish green with thick brown pollen (in 

 the specimens before me there is no "cupreous vitta" mentioned by 

 Melander and Brues in their description, but this is almost always a 

 variable character in this genus); pleurae dulled with gray pollen. 

 Abdomen green, the incisures narrowly black and edged with coppery 

 reflections. Hypopygium black; its lamellae rather large, oval, still 

 somewhat triangular in outline as they narrow into the stem, whitish 

 in the center, shading into yellow and then into black, often infus- 

 cated on more than half their surface, more yellow near the stem, 

 jagged and bristly at apex, otherwise fringed with blackish hairs. 



