318 NORTH AMERICAN TRYPETINA. 



third longitudinal vein not beset with bristles. Long. corp. 0.09 — 0.10 ; 

 long. al. 0.12. 



Syx. Trypeta mexicana Wiedemann, Auss. Zweifl. II, p. 551. 



Yellowish-gray. Front of a more vivid yellow, upon the lateral 

 margin with a rather indistinct whitish pollen ; the usual bristles 

 upon it are black ; those on the vertical margin pale yellowish. 

 Eyes rounded ovate; cheeks very narrow. Face distinctly 

 excavated, the anterior edge of the mouth is strongly drawn 

 upwards and rather projecting in the profile. The bristles of the 

 thoracic dorsum seem to be black, in reflected light they appear 

 brown ; in the middle of the dorsum there are but two pairs, the 

 first of which is very much advanced. The short pile upon the 

 thorax and the bristles upon the pleura? are pale yellowish. 

 Scutellum of a dingy-yellow at the tip, and with two bristles. 

 Abdomen black (a male from Texas shows a dingy yellowish 

 coloring at the basis), appearing almost grayish-black under a 

 very thin pulverulence, which does not prevent it from retaining 

 some lustre ; its pile is almost without exception pale yellowish. 

 Feet and coxa? rather saturate yellow, the pile and bristles upon 

 them yellowish. Wings hyaline with a brownish-black picture, 

 which is almost completely radiate towards the end; however, 

 the rays ending in the posterior margin are less developed and 

 less separated from each other than is the case in a normal pattern 

 of this kind ; the hyaline intervals between the rays distinctly 

 show that they owe their origin to confluent drops. The root 

 of the wings is but little spotted as far as the beginning of the 

 stigma and the end of the small basal cells; the adjoining portion 

 of the picture is almost without drops, so as almost to assume 

 the appearance of an oblique crossband, running towards the 

 posterior margin; the stigma at its basis contains a small hyaline 

 drop ; immediately beyond it, in the marginal cell, there are two 

 square hyaline spots, separated by a brownish-black line ; under 

 the first of them the submarginal cell contains a considerable 

 hyaline drop; the anterior side of the fourth vein shows two large 

 drops, the one a little before, the other a little beyond the small 

 crossvein ; the discal cell, on the fifth vein, contains three drops, 

 the first of which is the smallest and the second the largest; the 

 third posterior cell contains, besides the small hyaline spot at the 

 basis, four drops of considerable size, three of which are placed 

 at the posterior side of the fifth longitudinal vein ; in the poste- 



