1 38 .DIPTEEA. 



hairs on the thorax and on the sides of the abdomen are of a bright yellow, and not 

 whitish at all ; the scaly cross-bands on the second and fourth abdominal segments are 

 yellow ; the scales covering the enlargement at the base of the costa are black, and not 

 bright fulvous ; all the erect hairs on the surface of the thorax and of the abdomen are 

 less dense, and even seem to be shorter ; the black tufts of hair on the sides of the 

 fourth segment are distinctly shorter; in a word, the male of A.faustina, placed 

 alongside that of A. lateralis, has a much more hairy appearance. The legs of 

 A. lateralis are almost black; the costal cells are less hyaline, the veins forming them 

 seem to be stouter and are more clouded with brownish. I have little hesitation in 

 referring this specimen to A. lateralis, Say (Compl. Wr. ii. p. 59), although Say must 

 have had a female, because he does not mention the silvery scales at the end of the 

 abdomen. 



30. Anthrax moneta, sp. n., s . 



Altogether covered with a thin fur of white hairs, between which the black ground-colour is distinctly visible ; 

 the usual collar of fur in front of the thorax with a slightly yellowish tinge ; the sides of the abdomen with 

 a fringe of white hairs, except on segments 3, 5, and 6, which bear tufts of black hair ; the white hairs on 

 the sides of segment 4 form a more conspicuous tuft, reaching a little inwards ; a pair of tufts of snow- 

 white hair on each side of the end of the abdomen ; the surface of the abdomen shows no cross-bands, 

 except in some specimens, where the white hairs at the base of segment 2 are a little more dense, and thus 

 produce a faint appearance of a cross-band. Venter beset with a white tomentum and longer white hairs. 

 Pace densely beset with snow-white erect hairs, which, diminishing in length and density, encroach a little 

 upon the front, above the antennae ; otherwise the front has the usual covering of black, erect hair. 

 Antennae black ; third joint short-conical, with a long, slightly tapering style. Pace projecting very little ; 

 occipital orbits beset with white scales. Knob of the halteres yellowish-white. Legs black ; femora more 

 or less beset with whitish or somewhat yellowish scales ; front tibiae beset with spinules. "Wings hyaline ; 

 yellowish-brown at the root, before the basal cross-veins ; costal cell with a tinge of brownish-yellow at 

 the proximal end only ; the enlargement at the base of the costa has a covering of white scales, which, in 

 an oblique light, give a bright silvery reflection : similar scales cover the patagia or scapules above that 

 enlargement. 



Length 11-12 millim. 



Hah. Mexico, Northern Sonora (Morrison). Five males. 



31. Anthrax stenozona?, $. 



Anthrax stenozona, Loew, Centur. viii. no. 40 ( ? )'. 



Eab. United States, Illinois 1 . — Mexico, Northern Sonora (Morrison). 



I have a single specimen from Northern Sonora, which I doubtfully refer to this 

 species. The tomentum in front of the scutellum, on its sides, and the tomentose cross- 

 bands on segments 2, 3, 4 of the abdomen are not of a pure white, but have a slight 

 yellowish tinge. On the venter the first four segments have a rather even whitish 

 tomentum. In other respects the description agrees well ; the fringe of hairs on the 

 hind tibiae mentioned by Loew is present. In this species the tufts of black hair on the 

 sides of the abdomen are particularly long and conspicuous. 



