GYMNOPTERNUS. 83 



yellowish. The wings dusky with gray ; the small lamellae of the 

 hypopygium brown. 



Hab. Middle States. (Osten-Sacken.) 



•5. O. tristis, u. sp. % and 9 • — Atro-virens, pedibus nigris, genibus, 

 tibiis tarsorunique anteriorurn basi testaceis, tertio antennaruin articulo 

 nudo, alis nigricantibus. 



Black-green ; feet black, knees, tibise and the root of the four anterior 

 tarsi brownish-yellow, the third joint of the antennas bare ; wings black- 

 ish. Long. corp. 0.13—0.15. Long. al. 0.14—0.15. 



Resembles much not only the G. scotias, but also G. barbatulus. 

 Black-green, sometimes more metallic-black. Face of the % 

 black, of the 9 black-gray, the latter much broader than in the 

 % ; upon its lower part, in the 9 , several hardly perceptible black 

 hairs, which I did not observe upon the face of the %. Antennae 

 entirely black; the third joint broad, rather short, however some- 

 what longer in the % than in the 9, bare, that is to say, only with 

 the usual microscopic pubescence, which is very difficult to ob- 

 serve. The rather strong arista is also covered with this almost 

 imperceptible pubescence. Front dark metallic green ; the rather 

 whitish dust upon it becomes visible, when viewed in an oblique 

 direction. Cilia of the inferior orbit black. The scutellum has 

 besides the usual two bristles, also some shorter hair. Feet 

 black, tip of the coxae and trochanters in well matured specimens 

 hardly much paler; tip of the femora, the tibiae, and the root 

 of the four anterior tarsi brownish-yellow ; tip of the hind tibiae 

 brownish, the root of the hind tarsi sometimes brown. In less 

 matured specimens the lower side of the femora is mostly pitCh- 

 bfown. Cilia of the tegulae black. The small brownish-black 

 lamellae of the hypopygium are crescent-shaped, and adhere with 

 the concave side to the hypopygium, so that their true form cannot 

 be easily perceived ; on their convex side they are fringed with 

 small blackish hairs, but not jagged. The wings are comparatively 

 long, distinctly tinged with smoky black; the third and fourth 

 longitudinal veins show towards the end an indication of a slight 

 convergency; the hind transverse vein is comparatively distant 

 from the margin of the win<r. 



Hab. Sitka. (Wahlberg.) 



Observation 1. — Gymn. tristis is distinguished from Gymn. 



