276 THOMAS SAY FOUNDATION 



each side ; the hind edge of the fourth segment decid- 

 edly red ; first two segments with only lateral bristles ; 

 the third with median marginal pair and one lateral; 

 the fourth with a marginal row of about 16 ; fifth ster- 

 nite brown at base, with yellow, smooth, bare plate- 

 like sides, the bases angulated and bearing a few 

 black hairs, the opening V-shaped but somewhat 

 rounded at the bottom. 



Hypopygium red; first segment more or less 

 brownish, poUinose; generally without bristles be- 

 hind ; second shining yellow, globose, not bristly ; for- 

 ceps red, tips black, clothed with black hairs on the 

 attached part, around the tips with a very character- 

 istic cluster of short erect brownish or reddish hairs. 

 The tip is bent forward in a small hook but the gen- 

 eral shape of the forceps is straight. Accessory plate 

 yellow, the edge next the forceps thin, shining, drawn 

 out into a flat hook. Both pairs of claspers black, 

 shining, rather straight or only moderately hooked; 

 penis brown or reddish, very complex and almost in- 

 variably covered with a gelatinous substance making 

 its parts difficult to discern; the basal lobe is red and 

 of medium size, the distal one is large, mostly reddish, 

 bearing on the front side a long, complicated subdi- 

 vision which sometimes stands out very distinctly and 

 in other cases is closely applied. 



Legs black; femora stout; middle femur with al- 

 most comblike bristles below; middle tibia with two 

 stout bristles on the outer front side; hind tibia not 

 villous. 



Wings subhyaline; no costal spine; third costal 

 segment longer than the fifth ; first vein bare ; third 

 with a few hairs; apical cell widely open a consider- 

 able distance before the tip of the wing. 



Female. Front ,321 of head (average of five, — 

 .294, .317, .317, .322, .357), with the usual orbitals; 

 outer verticals as in male. Scutellum without apical 

 bristles. Genital segment red, shining, the opening 



