124 INSECUTOR INSCITI^ MENSTRUUS 



Siphoplagiopsis similis, new species. 



Length of body, 8 to 9 mm. ; of wing, 5 to 5.5 mm. Fifteen 

 females on flowers of Aster sp.. Grove Hill, Maryland, 

 October 30 to November 2, 1916 (Townsend) ; one male and 

 one female, Bladensburg, Maryland, September 16, 1915 (R. C. 

 Shannon), being respectively TD4566 and 4565. 



Black, with silvery to golden pollen. Head golden; occiput, 

 humeri, and pleurae brassy. Facial plate silvery-white. First 

 two antennal joints rufous. Palpi fulvous. Mesoscutum and 

 scutellum thinly brassy pollinose. Abdomen with brassy-silvery 

 pollen on intermediate segments, base or more of anal segment 

 brassy pollinose. Ground color of abdomen, often shining 

 through pollen, is polished black ; that of anal segment often 

 with a purplish tinge. The broad hind margins of intermedi- 

 ate abdominal segments, though revealing pollen in oblique 

 view, normally appear shining black. Wings clear, yellowish 

 on costobasal area. Tegulse white. 



Holotype, Cat. No. 20796, U. S. Nat. Mus., female. Allo- 

 type, male. 



Erythroargyrops, new genus. 



Genotype, Erythroargyrops elegans, new species. 



Differs from Argyreomyia as follows : Male. Eyes prac- 

 tically bare, with only indistinct scattered hairs. No proclinate 

 orbitals ; only one reclinate, being the hind one and more ap- 

 proximated to vertex. Outer vertical about half as long as 

 inner, which is weak. Frontalia not widened in the silvered 

 posterior area. All macrochastse weaker, but those of body 

 longer. Hind laterals of scutellum extremely long, apical hair- 

 like. No discals on abdomen, not even on anal segment. Me- 

 dian marginal of first segment hairlike, that of second seg- 

 ment strong. Third and anal segments with marginal row. 

 Apical cell narrower, ending but little before wingtip. 



Erythroargyrops elegans, new species. 



Length of body, 8.5 mm. ; of wing, 7.5 mm. One male, 

 Huascaray Ridge, Province of Jaen, Peru, 7,000 feet, Sep- 

 tember 21, 1911 (Townsend). 



