410 



XORTH AMERICAN DIPTERA 



Ouelletia, new genus 



Rather similar to Senotainia but the facial ridges are haired on 

 almost the lower half, the arista is wholly thickened and the face re- 

 treating. Differs from Euscnotainia in having the vibrisste more widely 

 separated and situated level with the anterior oral margin. Differs 

 from Euardba in the haired facial ridges and much narrower frontal 

 vitta. Front three-fourths as wide as either eye, slightly more than one- 

 third as w4de as the head, the parafrontals wider than the vitta, frontals 

 ending at base of antenna; two pairs of orbitals in the male and a 

 reelinate frontal in the orbital row, ocellars long; outer verticals weak. 

 Cheeks one-fifth as wide as the eye-height. Parafacials wide, setulose on 

 upper half. Palpi of moderate length. Facial depression very deep. 

 Antenna? elongate, the third segment very long and broad; arista wholly 

 thickened, the penultimate segment short. Acrostieals 1-1, weak, dorso- 

 centrals 2-3, the front ones fine; three pairs of marginal scutellars; 

 sternopleurals 1-1. Bend of fourth vein with a slight fold; base of third 

 vein with a single bristle. Squama3 produced inwardly. Abdomen oval, 

 without discals, the apical two segments with weak marginals. Black, 

 with whitish pollen; frontal pollen mostly brownish yellow, the meso- 

 notal pollen with brownish yellow tinge. Abdomen with a broad median 

 dark vitta and large black triangles on the second and third segments. 

 Genotype, 0. aristalis, new species, from Lauzon, Quebec, June. 



Phrissopodia praeceps Wiedemann. 



