254 DIPTERA OP NORTH AMERICA. [PART II. 



the first joint of the fore tarsi beset with black bristles, the two follow- 

 ing not shortened. 



9 . The black bands of the abdomen narrow and rather indistinct ; the 

 knob of the halteres yellow. Long. corp. 0.17 0.22. Long. al. 0.21 

 0.23. - , 



SYN. Psilopus melampus LOEW, Berl. Ent. Monatschr. VI, 215, 69. 



Male. Shining metallic-green, sometimes partly bluish-green, 

 the posterior part of the abdomen generally steel-blue. Proboscis 

 and palpi black. Face rather closely dusted with white, but with- 

 out hairs. Antennae black ; the second joint with numerous and 

 long black bristles. Arista distinctly dorsal, of a more than 

 moderate length. Front, besides the usual bristles, with a deli- 

 cate pubescence, which has near the upper corner of the eye a 

 black, towards the middle of the front a nearly whitish coloring. 

 Upper side of the thorax and the scutellum with long black 

 bristles. Pleura? with a greenish reflection and dusted with white. 

 Abdomen shining green, the anterior segments often, the hindmost 

 usually, steel-blue ; on the anterior margin of the single segments 

 there are sharply defined transverse bands, which are broader upon 

 the hind segments. Pubescence of the abdomen black, only on the 

 anterior portions of the lateral margin and of the venter, whitish ; 

 the black bristles before the hind margin of the single segments 

 are of a considerable, but not striking length. The small black 

 hypopygium has small black lamellae. Coxa3 and feet black ; fore 

 coxa? and all the femora with a bluish-green or blue reflection. 

 Fore coxa? with a considerable whitish pubescence, among which 

 there are some black bristles. Upon the under side of the femora 

 there is a long erect pubescence which is whitish only very near 

 the basis, otherwise black. Fore tibia? upon the outside with a 

 row of four, or at most five, long black bristles ; the last of which 

 is inserted at some distance from the tip of the tibias ; upon the 

 upper side with three or four quite short bristles, which may be 

 easily overlooked. The pubescence of the middle tibia? is some- 

 what more erect than that of the fore and hind tibiae, and upon 

 the upper side, especially towards the basis, longer; upon the 

 upper side there are four or five longer bristles, the last of which 

 is inserted at a considerable distance from the tip of the tibia? ; 

 upon the under side are four or five shorter bristles at equal dis- 

 tances. The hind tibia? have, besides the usual pubescence, upon 

 their outside about six bristles at equal intervals. The rather 



