8 PROCEEDINGS OP THE NATIONAL MUSEUM vol.74 



Male. — Front 0.22 of head width at vertex, almost the same at base 

 of antennae, thence widening quite rapidly. Cheek one-seventh of 

 eye height, wider posteriorly as the edge of the oral cavity slopes 

 upward toward epistoma. Vibrissae at oral margin, above the level 

 of lower curve of eye. Vibrissal axis equal to antennal, the 

 antennae attached above the level of eye middle, no ocellars; one 

 pair of verticals; frontals about 13, rather small, extending to level 

 of middle of second antennal joint. Antennae small, reaching 

 hardly halfway to vibrissae, third joint twice the second. Arista 

 subplumose on basal third, apical half or more bare. Pollen of head 

 pale yellow (probably faded) parafacials white; hairs of parafrontal 

 and cheek white, delicate. Antennae reddish, tip of third joint 

 infuscated. Palpi slender, yellow, not abbreviated ; proboscis small, 

 slender. 



Thorax black in ground color, pleurae with dense covering of 

 white plumose hairs which replace the hypopleural bristles and 

 extend upon the coxae; there are two stout black sternopleurals. 

 Mesonotum covered with similar but shorter plumose hairs, the 

 scutellum, however, has none except at the sides and there they ex- 

 tend along the lower edge nearly to the tip. The black bristles of 

 the mesonotum are conspicuous, as follows: Acrostichal 4, 4; dorso- 

 central 3, 3; humeral 4; posthumeral 1 (and 1 at front edge, inter- 

 humeral) ; presutural 1; supraalar 2; intraalar 2; notopleural 2 

 (?) ; scutellum with 2 large lateral, a very minute apical, the disk 

 with coarse black hair. Calypters large, bare, nearly white. 



Abdomen brownish-yellow, the ground color quite uniform, the 

 segments covered with thin whitish pollen uniformly distributed; 

 in some lights, a denser white crossband at base of second, third, and 

 fourth segments; all the sternites wholly covered; lateral margins 

 of second and third segments with one large bristle each, no others 

 on second, third with a pair of very faintly developed marginals 

 hardly larger than adjacent hairs; fourth with a marginal row 

 (broken off). Genital segments minute, retracted. 



Legs brownish-black, in some lights a little paler; front pulvilli 

 not enlarged: mid tibia with one bristle on outer front side, hind 

 with fine, appressed ciliation on outer hind side and one large on 

 outer front. 



Wings subhyaline, shorter than abdomen; fourth vein with 

 rounded, oblique bend; thence barely concave, ending a little before 

 apex; first posterior cell open; third vein with one distinct hair 

 at base, first vein bare; the costal segment before the second vein 

 equal to that beyond it; hind cross vein oblique, almost straight, join- 

 ing fourth at two-thirds the distance from small cross vein to bend. 



Length, 10 mm. 



