76 S. W. WILLISTON, M. D. 



OMMATIIS. 



Ominatius tibiulis. 



Ommatius tibialis Say, J. Acad. Phil, iii, 49: Compl. Wr. ii, fi3 ; Wiedemann, 

 Auss. Zw. Ins. i, 422, 6; Williston, Trans. Amer. Ent. Soc. vol. xi, pi. 2. fig. 12. 



•J, . — Length 16 mm. Black. Eyes in life green. Face thickly covered with 

 yellowish white pollen, the yellowish white mystax composed of hair, reaching 

 thinly nearly to the antenna. Antennae black. Dorsum of thorax smooth, bare 

 except the sparse and rather weak white bristles, with a broad black median stripe, 

 separated by a line on each side from two large spots, the one in front, the other 

 behind the suture; pleurse densely, nearly white poUinose. Abdomen black, 

 lightly pollinose on the sides and posterior parts of the segments, moderately 

 contracted on the sides in the middle. Halteres light j'ellow. Wings hyaline, 

 lightly blackish tinged on the outer part, on the exterior anterior part with a 

 distinct yellowish tinge; costa strongly thickened and bent forwards beyond the 

 tip of the auxilary vein. Legs chiefly yellow, but variable, the femora more or 

 less black, the hind pair most so, sometimes almost wholly black, the front pair 

 least so. sometimes almost wholly yellow, tips of the tibiaj, most especially the 

 hind pair, which may be only yellow at the base; tarsi black, the front and mid- 

 dle pairs yellow at the base. In the female the costa of the wings is simple, not 

 thickened or curved, otherwise as in the male. 



Hah. — Penna, Conn., Mass. 



Four specimens from New England. A greasy female from Georgia 

 that I can not otherwise separate, has the legs, except the tip of the 

 hind tarsi, wholly light yellowish red. 



