236 NORTH AMERICAN TRYPETINA. 



medium length, broad and broadly truncate ; wings with narrow pale 

 brownish rivulets and with a fourth longitudinal vein which is not 

 curved forwards at the tip. Long. corp. 0.18, cum terebra 0.23; long, 

 al. 0.20. 



Pale clay -yellowish. The head resembles that of T. fratria in 

 shape, only the front is somewhat broader and the vertical diame- 

 ter of the eyes is a little smaller; the anterior edge of the mouth 

 is more projecting. On the border of the front the described 

 specimen bears, on each side, three long, but rather weak black 

 bristles. Antennae of a more saturate yellow, not reaching the 

 edge of the mouth ; their third joint is rounded at the tip ; arista 

 blackish, yellow towards the basis, with a very short pubescence. 

 Rostrum and palpi pale yellow, the latter not reaching beyond 

 the anterior edge of the oral opening. Thoracic dorsum with 

 a very thin, whitish bloom, only the double middle stripe and 

 the narrow lateral stripes not pollinose, rather shining and 

 somewhat darker than their surroundings. The posterior end 

 of the thoracic dorsum and the scutellum likewise without pol- 

 len, shining, very pale yellow ; a not very broad yellowish stripe 

 runs from the humeral corner to the root of the wings. The 

 scutellum is convex and not very large; in my specimen it has 

 three bristles on one side and only two on the other, so that I 

 cannot say whether the normal number of the bristles of the 

 scutellum is six or four. The bristles of the thorax and of the 

 scutellum, as well as the short pile of the thoracic dorsum, are 

 black. Metathorax distinctly infuscated on its superior margin 

 and its middle line. Abdomen shining, with short black pile; 

 the third and fourth segments have, each at its basis, a chestnut 

 crossband, interrupted upon its middle, while upon the second 

 segment only a lateral beginning of such a stripe is indicated by 

 a chestnut-brown spot. The very broad ovipositor is flat, almost 

 as long as the last three abdominal segments taken together, very 

 broadly truncate and infuscated at the end. The front femora 

 are sparsely beset with bristles upon the upper and under side ; 

 the middle femora are entirely without bristles ; upon the hind 

 femora, likewise, there are only a few bristle-like hairs before the 

 end of the upper side ; the upper side of the hind tibiae is merely 

 beset with exceedingly short bristle-like hairs. Wings of the 

 usual shape, hyaline, with a pale-brown picture; it consists: 1. 

 In an oblique half crossband running from the humeral crossvein 



