Chrysogaster. 



101 



vein rather thick and a little seamed. Stigma yellow but with just 

 the base darkened or blackish. 



Female. Frons and epistoma very broad, in the height of the 



Fig. 37. Antenna of O. geniculafa c?, from the inside. X 80. 



antennæ about twice as broad as the diameter of the eye; frons 

 otherwise chiefly as in elegans, but more punctate, the middle channel 

 less distinct. Antennæ a Uttle larger than in the male. Thorax more 



Fig. 38. Wing of O. geniculata d". 



conspicuously haired than in elegans. Fourth abdominal segment with 

 a distinct wart in the middle of the hind margin, the fifth with an 

 impression on each side at the hind margin. Hind femora not black 



Fig. 39. Wing of O. geniculata 9- 



setulose. Wings less tinged than in the male or almost not tinged; 

 upper marginal cross-vein distinctly recurrent and the lower a little 

 angular with the angle inwards. 



