170 DIPTERA OF NORTH AMERICA. 



Gen. V. SCATELL.A ROB. DBSV. 



This genus contains only smaller and generally not, metallic 

 species. Front and face very broad ; eyes rounded ; face usually 

 very convex, hairy and bristled ; border of the mouth ciliated ; 

 opening of the mouth wide; clypeus concealed; cheeks moderately 

 broad; mentum swollen. Second joint of the antennae nftt ungui- 

 culated ; antennal bristle with fine, usually very short pubescence. 

 Claws curved, pulvilli distinct. Costal vein of the wings reaching 

 to the tip of the fourth longitudinal vein ; the small transverse 

 vein generally almost exactly beneath the tip of the first longitudi- 

 nal vein ; the posterior transverse vein not approaching the border 

 of the wing. The nearest genus is Ccenia, differing, however, from 

 Scatella by the pectinated bristle of its antennas. 



1. S. favillacea LOEW. 9 . Cinerea, facie alba, alis cinereo-hyalinis, 

 obsolete quadriguttatis. 



Ashy-gray ; face white ; wings grayish-hyaline with four indistinct clear 

 drops. Long. corp. 0.12 0.13. Long. al. 0.13. 



This species resembles most the European S. sorbillans Hal., 

 which is identical with S. argyrostoma Stenh., but differs from it 

 by its more considerable size, more roughly haired face and gray 

 color of the dust on the posterior part of the cheeks, on the infe- 

 rior part of the occiput, on the pleurae and under side of the abdo- 

 men, on all which parts it is whitish in that species ; S. favillacea 

 wants also the clear drop lying beyond the posterior transverse 

 vein in S. argyrostoma. The upper side of the whole body is 

 covered with grayish-brown dust, which on the middle of the tho- 

 rax and on the scutellum does not conceal the shining of the ground 

 color ; the large spot lying on the middle of the front is shining 

 greenish. Face very convex, dusted with snowy white, with rather 

 rough hair and the usual row of curved upwards bristles. Open- 

 ing of the mouth wide, with distinct black cilia on the borders. 

 Antennas black ; the pubescence of the bristle is a little longer 

 and more distinct than in most species of this genus. Upper side 

 of the thorax not distinctly striped. Pleurae dusted with yellowish- 

 gray, on their superior border with rather brown dust. Under 

 side of the abdomen, femora, and upper side of the tibiae with gray 

 dust. Wings clouded with grayish, having black veins ; of the 

 five clear drops, peculiar to so many species of this genus, that 



