24 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.60. 



noted in the succeeding description, and is sufficient to cover the 

 color differences attributed to Say's two species. 



Female. — Rostrum long, extended proboscis longer than antenna ; 

 head black ; thorax yellow to rufous more or less marked with black 

 on humeri, pleura, combs and scutellum; abdomen velvety brown 

 to black, genitalia chiefly yellow; front and mid coxae and corre- 

 sponding, sometimes all, femora yellow to rufous; tibiae and tarsi 

 brown to black ; short sparse hair on head and thorax, more copious 

 on abdomen and legs chiefly concolorous with the surface of origin; 

 wings and veins dusky, darker costally. 



Length of wing, 5-6 mm. 



Specimens examined are from New England, Minnesota, Mary- 

 land, Virginia, North Carolina, and Florida. 



DILOPHUS STIGMATERUS Say. 



D. [iZopft-ws] stigmaterus Say (Thomas), Desc. Dipt. U. S., Jouru. Acad. 

 Nat. Sci. Phila., vol. 3, 1823, pp. 79-«0 ; Compl. Writings, vol. 2, 1859, pp. 

 70-71 [Missouri]. 



Male. — Rostrum about as long as the short antenna ; eyes reddish 

 with short dark hair; remainder of head and body shining black 

 with a moderate amount of longer pale hair; legs varying from 

 3'ellowish rufous to brownish black with abundant pale hair ; genital 

 segment with only a shallow cleft, superior plate about three times 

 as wide as long, the hind margin moderately convex ; knob of halteres 

 dark, stalks pale; wings nearly hyaline, veins of costal region and 

 small rather indefinite stigma brown. 



Female. — Rostrum about as long as the short antenna; extended 

 mouth parts three times as long ; head black the rostrum sometimes 

 yellow to rufous; thorax yellow to rufous, combs, pleura and scu- 

 tellum more or less touched with darker; abdomen velvety brown, 

 genitalia more or less tipped with yellow; legs yellow to rufous, 

 spines of front tibiae and tips of tarsal joints (apical joints of tarsi 

 sometimes entirely) black; knob of halteres dark, stalk pale; wings 

 and veins yellowish hyaline, veins of costal region and large distinct 

 stigma brown. 



Length of wing, 3.5-5 mm. 



Specimens examined are from Wisconsin, Colorado, and New 

 Mexico. 



DILOPHUS STRIGILATUS. new species. 



Male. — Shining black (legs sometimes brownish), with sparse pale 

 hair ; eyes reddish with short erect black hair ; stalks of halteres pale ; 

 wings hyaline, veins near costa, and stigma dark brownish to black; 

 genital segment cleft somewhat less than half its length, approach- 

 ing in this respect D. tibialis., from which it differs in smaller size — 

 wing 4 mm. or slightly less, as contrasted to 5-6 mm. in the former. 



