psilopus. 255 



slender fore tarsi about once and a half the length of the tibiae ; 

 their first joint is much longer than the following taken together, 

 and is fringed upon its outside with six or seven lung bristles, 

 inserted somewhat closer towards its tip ; the four Last joints of 

 the fore tarsi are of a gradually decreasing length and of an en- 

 tirely plain structure. Middle tarsi plain, about once and a third 

 the length of the tibia), their first joint about l£ the length of 

 the following taken together. It has upon its front and upper side 

 an exceedingly short and therefore not quite easily perceptible 

 fringe-like black pubescence. Hind tarsi shorter than the hind 

 tibia?, the fourth joint about 1^ the length of the following 

 taken together. Halteres brownish-black. Tegula? with a very 

 broad black margin and with long black cilia. Wings hyaline 

 with the usual siphon-like picture; both bands forming this pic- 

 ture are perpendicular, generally of only middle breadth, always 

 connected on the fore margin, sometimes also upon the fourth 

 longitudinal vein, and abbreviated before the hind margin of the 

 wings. The first longitudinal vein reaches somewhat beyond the 

 middle of the anterior margin ; the anterior branch of the fourth 

 longitudinal vein diverges at an angle of about *T0°, and turns 

 afterwards at a somewhat rounded right angle towards the mar- 

 gin, which it reaches before the extreme apex, near the tip of the 

 third longitudinal vein ; the hind transverse vein rather oblique, 

 only little sinuated. 



Female. It resembles the ^ in the coloring of the body and of 

 the feet, as also in the neuration, and the picture of the wings. The 

 glabrous face is dusted somewhat closer ; the bristles on the second 

 joint of the antenna) are distinctly shorter than in the other sex; 

 the bristles upon the thorax and scutellum arc shorter, and those 

 before the posterior margin of the abdomen much shorter than in 

 the male. There is only a vestige of a black band on the basis of the 

 segments of the abdomen. Feet plain. Pubescence upon the 

 under side of the femora much shorter than in the male. Fore tibiae 

 upon the upper side generally with only two short bristles, upou the 

 outside with three, but little longer ones. Hairs on the middle 

 tibiae not longer than usual; upon their upper side there are 

 generally only three black bristles, two near the basis and one 

 beyond the middle; upon the under side there are generally four 

 small bristles at equal intervals. Hind tibiae as in the £ . Tarsi 

 shorter, plain; the first joint of the fore tarsi without bristles 



