ARGYRA. 129 



black hairs. Femora brownish-black with yellow tip ; their black 

 hairs are comparatively long, especially upon the under side of the 

 four anterior femora. Tibiae yellow, only the extreme tip of the 

 hind tibiae blackish-brown ; the fore tibiae are beset with four or 

 five bristles only upon the upper side ; the small bristles upon the 

 middle and hind tibiae are likewise but short and very scarce ; the 

 hind tibiae are not in the least thickened. The four anterior, tarsi 

 are brownish-yellow at the basis, a little further blackish-brown, of 

 plain structure, the first joint upon the under side without bristles. 

 Hind tarsi entirely black. Tegulae mostly black with black cilia, 

 Wings hyaline, a little more distinctly tinged with gray than in 

 A. nigripes. 



Rob. Sitka. (Sahlberg.) 



4. A. iuintlta Loew. % . — Scutello nudo, pedibus totis pallide flavi- 

 cantibus, metatarso maris postico sirnplici, brevissime piloso. 



Scutellum bare; the whole feet pale-yellowish; the first joint of the hind 

 tarsi of the male simple, with very short hair. Long. corp. 0.16. Long. 

 al. 0.14—0.15. 



Syx. Argyra minuta Loew, Neue Beitr. VIII, 46, 2. 



Male. Face very narrow, silvery-white. Palpi black. Pro- 

 boscis brownish-black. Antennae black, third joint more blackish- 

 brown ; arista distinctly inserted before its tip. Front silvery- 

 white. Cilia on the upper orbit black, very short and delicate ; 

 cilia of the lateral and inferior orbits white. Thorax and scutel- 

 lum shining green, covered with white, not very thick dust, which 

 conceals the ground color at the utniost only in the vicinity of the 

 shoulders. Scutellum, with the exception of the usual bristles, 

 bare. The ground color of the abdomen appears to be blackish- 

 green, is however so thickly covered with white dust that it can- 

 not be distinctly perceived ; the second segment of the abdomen 

 has on each side a very large rounded yellow lateral spot ; the 

 third segment has a similar spot, but smaller. The very small 

 and narrow lamellae of the hypopygium are yellowish-brown and 

 but little hairy. Fore coxae yellowish-white, with white hairs 

 and black bristles. Middle and hind coxae also yellowish-white, 

 but blackened from the basis to a considerable extent ; hairs and 

 bristles black ; feet pale-yellowish, only the end of the hind femora 

 has a vestige of infuscation on its upper side. The hairs upon 

 9 



