psilopus. 257 



somewhat gray, by being slightly dusted with whitish. Pubescence 

 of the abdomen more erect and longer than usual, black, only 

 whitish on the anterior part of the lateral margin and of the venter. 

 The small hypopygium black, with blackish-brown lamellae. Coxa) 

 and feet black ; coxa) with a greenish reflection, rather closely dusted 

 with white ; the foremost with a distinctly whitish pubescence and 

 with some stout black bristles. Under side of the femora with a 

 delicate, long, erect pubescence, which, quite near the tip of the 

 femora, has a black, otherwise everywhere a whitish coloring. Fore 

 tibiae yellowish-brown, upon the upper side dark-brown, and near 

 the basis almost black, upon the outside fringed with not very nu- 

 merous, but proportionally long black bristles. Middle tibiae black, 

 only yellowish-brown at the end of the inner side, ciliated upon 

 the front side with a regular row of moderately long black bristles ; 

 upon the upper side fringed with moderately long and somewhat 

 erect black hairs, upon the first third of the hind side with some 

 moderately long black bristles, at the tip with three longer black 

 bristles, of which one is inserted on the inner side, the two others 

 upon the front side. Hind tibiae entirely black, rather long, with 

 somewhat coarse black hairs and a few short black bristles, which 

 are inserted between the upper and the hind side. Fore tarsi slender, 

 nearly twice the length of the tibise ; the first joint alone is some- 

 what longer than the tibia and about once and a third the length of 

 the four following taken together, the length of which is rapidly 

 decreasing ; no unusual pubescence or bristles are to be seen on the 

 fore tarsi. Middle tarsi twice the length of the tibiae ; their first 

 joint alone much longer than the tibia, about once and a half the 

 length of the four following taken together, brownish-yellow, 

 straight, somewhat stouter than usual, upon its upper side regularly 

 ciliated with erect, minute, black hairs ; the four last joints black, of 

 decreasing length. Hind tarsi entirely black, much shorter than 

 the tibiae ; first joint once and a half the length of the four follow- 

 ing taken together ; second joint about as long as the three 

 following taken together ; these are rather short, of almost equal 

 length and somewhat flattened, so that the end of the hind tarsi 

 looks somewhat stouter than usual. Halteres black ; tegulae with 

 a broad black border and long black cilia. Wings hyaline, propor- 

 tionally larger than in P. patibulatus, with the usual siphon-like 

 black picture ; the two black bands not particularly broad, as 

 usual, shortened behind, only connected on the fore margin ; the 

 17 



