6 PROCEEDINGS OF THE NATIONAL MUSEUM vol.68 



Type-locality. — Okeanskaj a, Siberia. 



Described from one female (type) and two males (one allotype) , 

 collected August, 1923, by T. D. A. Cockerell. The type and allotype 

 were collected August 5th. 



Type, allotype, and par atyjje.— Cut. No. 27617, U.S.N.M. 



RHOGOGASTER KUDIANUS, new species 



This species seems to be intermediate between R. vi/ridis (Lin- 

 naeus) and R. dissimulans (Kincaid). In general color it is much 

 like Kincaid's species, but it differs from it in the more deeply 

 emarginate clypeus and the dark markings at the apices of the 

 tarsi. It may readily be separated from viridis by the complete 

 absence of black on the abdomen, a slight difference in the shape of 

 the sheath and shorter antennae. 



Female. — Length, 9.5 mm. Labrum broad, the apical margin 

 almost truncate, anterior margin of the clypeus with a deep, sub- 

 quadrate emargination, the lobes broad and truncate ; head without 

 punctures; postocellar furrow straight; postocellar area more than 

 tATo times as broad as long ; occipital carina sharply defined ; antenna 

 slender, a little longer than the head and thorax, the third joint 

 subequal with the fourth and fifth; thorax smooth; second inter- 

 cubit'us sinuate; fourth abscissa of cubitus one-third as long as the 

 third; sheath stout, strongly convex below, the apex narrowly 

 rounded. Uniformly pale-yellow (green in life) ; flagellum, except 

 the two basal joints beneath, scape and pedicellum above, a U-shaped 

 mark on the frons, the small spot inclosing the anterior ocellus, 

 suture of prescutum, sides and depressed area of scutum, black ; legs 

 color of the body; apices of the four anterior femora above, the 

 posterior femora with a complete narrow line above, narrow lines 

 on all tibiae above, apices of all tarsi, black; wings clear hyaline, 

 strongly iridescent ; venation yellow ; costa, basal, median, discoidal 

 and anal veins, black. 



Type-locality. — Kudia River, Amagu, Siberia. 



Described from a single female collected July, 1923, by T. D. A. 

 Cockerell. 



Type.— Csit. No. 27618, U.S.N.M. 



SIOBLA RUFICORNIS (Cameron) 



One female from Kudia River, Amagu, Siberia, collected July, 

 1923, by T. D. A. Cockerell. 



This specimen agrees with Cameron's and Kirby's descriptions, 

 except the hind femora are entirely black. 



