10 PROCEEDINGS OF THE NATIONAL MUSEUM vol.73 



BELVOSIA SLOSSONAE Coqnillett 



Belvosia slossonae Coquillett, Proc. Acad. Nat. Sci. Phila., vol. 47, 1895, 

 p. 312; Revis. Tachin., 1897, p. 84. 



Male. — Front 0.37 to 0.41 of the head width at vertex, inner mar- 

 gins of eyes diverging only slightly, so that the front is nearly as 

 wide as the face, rather prominent at the antennae. Parafrontals 

 silvery on lower part, translucent brownish above except in diagonal 

 view; frontal bristles in about three rows and there are in addition 

 two pairs of proclinate orbital bristles as in female; face, parafacial, 

 cheek, and posterior orbit silvery pollinose, the small hairs below the 

 frontals are pale; cheek with pale hairs, and at the lower edge an 

 irregular double row of black bristles. Palpi yellow; beard white. 

 Antennae black, first two joints brown, third joint elongated and 

 somewhat swollen at the origin of the arista, more than four times 

 the length of the second joint. Arista thick and flattened, broad to 

 the tip, which is bluntly rounded; its total length is about three- 

 fourths of the third antennal joint. Vibrissae quite close to the oral 

 margin, the distance being only half the length of the second anten- 

 nal joint; facial ridges with stout bristles for more than two-thirds 

 their height, almost up to the arista. There are some white hairs 

 on the ridges outside of the bristles. 



Thorax black, densely cinereous pollinose, with four indistinct 

 blackish stripes; pleurae with some pale, delicate hairs mixed with 

 darker and larger bristles; scutellum black, the margin slightly 

 reddish. 



Abdomen black, second segment with gray pollen, fading out near 

 the middle in most angles, but in certain directions visible almost to 

 the hind margin; third segment about the same, but with a more 

 distinct black hind border; fourth segment with denser and slightly 

 more yellowish pollen on the basal two-thirds, mixed with a consid- 

 erable number of erect black hairs. None of the pollen of the abdo- 

 men is very deep yellow. First and second segments with one pair 

 of median marginals, third and fourth with a marginal row. 



Wings brown, more yellow basally ; both calypters white, contrast- 

 ing with the wing. 



Legs black, front pulvilli nearly as long as last two tarsal joints,* 

 hind tibia with a sparse, suberect row of about 13 bristles, the largest 

 just below the middle. 



Female. — Front at vertex 0.38 to 0.41 of the head width; front not 

 so brown as in the male; third antennal joint shorter and second 

 longer, so that the third is hardly more than twice the second; the 

 facial ridges are much less bristly than in the male. 



Length, 9-12 mm. 



Described from a series "of 5 males and 13 females, collected by 

 C. H. T. Townsend at Miami, Fla., October 26-November 14; 2 



