116 DIPTERA. 
the hind margin of the second segment a pair of macrochets, on that of the third and fourth segments a 
row of macrochete ; ventral surface black. Legs black; front femora with two rows of regularly placed 
bristles ; the middle and hind femora with some bristles ; front tibia outwardly with short bristles ; some 
long bristles on the outside of the middle tibiz and one on the inner side; hind tibie outwardly with a row 
of short bristles and with one longer bristle; foot-claws and pulvilli short. Tegule whitish. Wings © 
greyish-hyaline; small cross-vein on the middle of the discal cell; curvation of the fourth vein rect- 
angular; apical cell trigonal, the apical cross-vein nearly perpendicular and straight ; posterior cross-vein 
very slightly convex, a little beyond the middle between the small cross-vein and the curvation of 
the fourth vein. 
Hab. Mexico, Cuernavaca (H. H. Smith). 
A single female specimen. 
PROSPHERYSA*%, gen. nov. 
Head at least as broad as the thorax; front usually a little prominent; face retracted; facial ridges with a 
row of bristles ; vibrissee inserted at the oral margin or at a little distance above it; eyes bare. Antenns 
as long, or nearly as long, as the face; third joint at least three times as long as the second; arista bare, 
in some species slightly pubescent. Proboscis prominent; palpi cylindrical. Abdomen conical or oval; 
basal segment usually shorter than the following one; second and third segments with marginal, some- 
times also with discal, macrochetz; male genitals more or less conspicuous. Legs bristly. Wings. 
sometimes with a costal spine ; curvation of the fourth vein angular, without appendage, in some species 
faintly prolonged by a fold in the wing’s surface; apical cell opened at some distance before the tip of 
the wings. 
This genus is allied to Phorocera, but differs from it in the eyes being bare. 
The following species belong to it :— 
1. Second and third abdominal segments, or at least the third, 
with discal and marginal macrochete . . .... . 2. 
Second and third abdominal segments with marginal macro- 
chete only. 2. 2. 2 1 ww ew ee eee ee 
2. Arista pubescent; wings with a costal spine; apical cell 
concave . 6 ee ew we ee we ew ee ee. mutans, v. d. Wulp. 
Arista bare; wings without a costal spine 3 apical cross-vein 
nearly or quite straight. . . . : . 3. 
3. Anal segment ochraceous; arista thickened to beyond the 
middle . . .... . soe 8 ee ee ew 6 Ochricauda, v. d. Wulp. 
Anal segment otherwise coloured ; arista thickened at most 
to the proximal half . re 
4. Posterior cross-vein straight. . . . . .... . . «5, 
Posterior cross-vein distinctly curved . . . oe 6. 
5. Abdomen shining black, with whitish front borders to the 
segments . . . . se 2 2 2 2. trifasciata, v. d. Wulp. 
Abdomen grey, with blackish reflections coe ee ew. ingloria, v. d. Wulp. 
6. Anusrufous . . . . 1. 1 1 ee ee ee wk comosa, v. d. Wulp. 
Anus shining black. . . . . . . ww eet contigua, v. d. Wulp. 
* xpoopepys (standing near). 
