psilopus. 259 



black, whitish only on the anterior part of the lateral margin and 

 of the venter. The black bristles before the hind margin of the 

 single segments of a very moderate Length. The very small bypo- 

 pygium blackish; the blackish-brown lamellae \ny narrow, nearly 

 filiform. Coxae black or brownish-black, somewhat dusted with 

 white, the foremost with a rather distinct white pubescence and 

 with a few black bristles. Femora black, with a green reflection, 

 the extreme tip of the foremost ones yellowish, that of the hind ones 

 brown ; their lower side fringed with minute, erect whitish hairs, 

 which are much more scarce and longer on the hind femora. The 

 fore femora have, upon their hind side near the tip, three successive 

 black bristles. Fore tibiae yellowish, upon the first half of their 

 hind side with three rather considerable black bristles of a decreas- 

 ing length. Middle tibia; yellowish, with a few black bristles at 

 the tip, otherwise only .with some very short minute black bristles. 

 Hind tibiae dark-brown, with the usual black hairs, nearly without 

 any apparent bristles. Fore tarsi slender, over If the length of 

 the tibiae; their first joint is yellowish-brown, darker at the tip 

 and not quite as long as the tibiae, also hardly longer than the 

 four following joints taken together ; it has upon its hind side three 

 rather considerable bristles of increasing length ; the four follow- 

 ing joints of the fore tarsi are blackish-brown, more yellowish-brown 

 at the basis, at least once and a half the length of the tibiae ; their 

 first joint nearly as long as the tibiae and once and a third the length 

 of the following joints taken together, which are of a decreasing 

 length ; no unusual pubescence or bristles on the the middle tarsi. 

 Hind tarsi brownish-black, distinctly shorter than the tibiae ; first 

 joint hardly longer than the four following joints taken together: 

 the length of the latter is rapidly decreasing, Halteres dingy- 

 brown. Tegulae with a narrow black margin and black cilia. 

 Wings hyaline with the usual siphon-like blackish picture; the 

 two bands are perpendicular, of medium breadth, still rather dis- 

 tant from each other, connected only on the anterior margin : the 

 anterior branch of the fourth longitudinal vein diverges from it at 

 an angle of about 70° and turns afterwards towards the margin 

 of the wing at a but little rounded angle ; it reaches it before the 

 apex, near the third longitudinal vein ; posterior transverse vein 

 moderately oblique and nearly straight. 



Female. Face likewise without hairs. The bristles on the 

 second joint of the antennae much shorter than in the male ; the 



