248 DIPTERA OF NORTH AMERICA. [PART II. 



Syn. Dolichopus sipho Say. Journ. Ac. Pliilad. Ill, 84,1. 

 Psilopus sipho Wiedemann, Auss. Zweifl. II, 218, 9. 

 Psilopus gemmifer Walker, List, III, 646. 

 Psilopus sipho Loew, Neue Beitr. VIII, 83, 1. 



Saturate green, often bluish-green, steel or even purplish-blue, 

 seldom gold-green, always very shining. Face without hairs, its 

 upper part but little convex and separated from the lower part by 

 •i shallow impression. Proboscis brownish-yellow. Antenna? 

 black ; the pubescence of the second joint only of moderate 

 length ; third joint rounded ; arista distinctly dorsal ; not par- 

 ticularly long. Abdomen with black transverse fasciae on the 

 fore margin of the segments, which are so narrow in the 9 , that 

 they are entirely concealed beneath the hind margin of the pre- 

 vious segment ; in the J* the hind segments of the abdomen are 

 often gold-green ; the same is sometimes also the case in the 9 , 

 where this gold-green color sometimes also reaches the anterior 

 segments of the abdomen. The pubescence of the abdomen is 

 generally black ; in the male it is whitish upon the first segment, 

 on the basis of the second and of the third segments, and on the 

 anterior half of the lateral margin ; in the 9, the pubescence of 

 which is in general shorter, minute whitish hairs are to be found 

 only upon the first segment and on the anterior part of the lateral 

 margin, which hairs are less perceptible than in the J\ The black 

 bristles before the hind margin of the segments of the abdomen are 

 only of a moderate length. Hypopygium small, black ; lamella? 

 small, black or brownish-black, ciliated with black. Fore coxa? 

 yellowish, with a delicate white pubescence and a few black bristles 

 near their tip. Middle and hind coxa?, including the trochanter, 

 dark. Feet yellowish ; all the femora are beset with delicate, 

 minute whitish hairs upon the under side, which are distinctly longer 

 in the <£ than in the 9 ; the fore femora have a row of four to five 

 black bristles upon the hind side ; on the middle and hind femora a 

 few thorn-like minute black hairs are to be found upon the hind side, 

 as well as upon the anterior side before the tip. Fore tibia? entirely 

 yellow ; in both sexes, three small bristles are generally to be found 

 upon the upper side ; and whilst there are likewise but three upon 

 their outside in the 9 , in the £ , about six much longer bristles are 

 usually extant. The fore tarsi are yellow at the basis, but be- 

 come black already before the end of the first joint ; in the J 1 they 



