144 DIPTERA OF NORTH AMERICA. 



bases of all the tarsi reddish-yellow ; wings blackened towards the costa ; 

 knob of the poisers white. Long. corp. 0.13. Long. al. 0.14. 



Black ; front, thorax and scutellum thickly dusted with ashy- 

 gray with a fuscous tinge. Antennas reddish-yellow ; the bristle 

 with scattered pectinations. Face thickly dusted with whitish- 

 gray, rather of uniform breadth, with more numerous bristles on 

 the sides than in most other Psilopce, generally slightly convex, 

 with the lower part a little projecting, but towards the border of 

 the mouth again remarkably receding, rendering thus the opening 

 of the mouth smaller than is usual in this genus. Proboscis and 

 tarsi blackish. Pleura? brownish-black, shining. Abdomen shin- 

 ing black with very little visible dust. Legs shining black ; tarsi 

 reddish-yellow, the three last joints of the foremost, and only the 

 two last of the hindmost ones being black. Poisers with brown pe- 

 tioles and white knob. Wings clouded with grayish-black, becom- 

 ing gradually black towards the costa; the posterior transverse vein 

 scarcely perceptibly margined with blackish; the second segment of 

 the costal vein more than half as long again as the third. 



Hob. Cuba. (Poey.) 



5. P. caeruleiveutris LOEW. 9- Capite thoraceque cinereis 

 opacis, abdomine chalybeo nitido, antennis palpisque' flavis, pedibus 

 nigris, tarsis posterioribus rufis, alis hyalinis vitta latissinia atra, rnar- 

 gini antico contigua, pictis. 



Head and thorax opaque ashy-gray, abdomen shining steel-blue ; antennse 

 and palpi yellow ; legs black, posterior tarsi red ; wings hyaline, with an 

 exceedingly broad, deep black longitudinal stripe on the costa. Long, 

 corp. 0.15. Long. al. 0.16. 



Front ashy-gray. Antenna? reddish-yellow. Face whitish-gray, 

 slightly convex, with rather slender small bristles on the sides ; 

 oral cavity small; clypeus projecting a little beyond the border of 

 the oral margin. Palpi pale yellowish, a little broader than usual. 

 Upper side of the thorax ashy-gray without any gloss. Pleurae 

 thinly dusted with grayish, and consequently blacker and rather 

 glossy. Scutellum dusted with brown, shining black at the tip. 

 Abdomen shining steel-blue ; the first segment but little shortened, 

 the second as long as the first, the three following longer ; even 

 the narrow sixth segment is distinctly visible. Legs black, the 

 foremost with dark brown knees ; middle and hind tarsi yel- 

 lowish-red with blackish-brown tip ; the fore tarsi have only 



