206 DIPTERA. 
Front broader than the eyes, blackish ; frontal bristles not descending beneath the root of the antenne ; face 
and cheeks somewhat whitish: on the cheeks, close to the margin of the eyes, a row of four or five long 
bristles. Antenne black, nearly as long as the face; third joint rather broad, four times as long as the 
second ; arista thickened to near the tip. Abdomen conical; macrocheete only on the hind margins of 
the segments. Legs black; the femora beneath and the tibie outwardly with rather long bristles. 
Tegule whitish. Wings with a short costal spine, greyish-hyaline, blackish-brown along the costa and 
on the exterior cross-veins; apical cell closed and rather long-petiolated ; small cross-vein on the middle 
of the discal cell ; curvature of the fourth vein rectangular; apical and posterior cross-veins perpendicular 
and straight, the latter in the middle between the small and the apical cross-veins; third vein with a row 
of short bristles. 
Hab. Mexico, Atoyac in Vera Cruz (H. H. Smith). 
A single female specimen. 
LEUCOSTOMA. 
Leucostoma, Meigen, in Illiger’s Magazin, ii. p. 280 (1808). 
The principal characters of this genus are the following:—Face shorter than the 
front; eyes bare; antenne short, the third joint being scarcely longer than the second ; 
abdomen conical, in the female ending with a small forceps, marginal macrochete only 
present ; foot-claws and pulvilli elongate in the male; tegule large; wings with the 
apical cell closed and rather long-petiolated, the posterior cross-vein nearly in the 
middle between the small cross-vein and the curvature of the fourth vein. 
In the Central-American collection before me there are representatives of two species 
belonging to the genus Leucostoma,-one of which seems to agree with the description of 
L. analis, Meig., an insect hitherto only known from South Europe. 
1. Leucostoma analis? 
Tachina analis, Meigen, Syst. Beschr. europ. zweifl. Ins. iv. p. 290. no. 91. 
Leucosioma analis, Schiner, Faun. Austr., Dipt. i. p. 548. 
Tachina tetraptera, Meigen, loc. cit. no. 92, t. 41. fig. 25. 
Shining black ; head whitish; in the male the third and anal segments greyish ; wings hyaline, yellowish at 
the base; small cross-vein on or nearly on the middle of the discal cell. 
Length 4°5-5°5 millim. . 
Front narrowed behind and there narrower than the eyes; frontal band black; frontal bristles descending to 
a little beneath the root of the antenne; vibrisse inserted at some distance above the oral margin ; 
posterior orbits of the eyes long-haired. Antenne black; second joint with a rather long bristle; third 
Joint one and a half times as long as the second; arista gradually tapering towards the tip. Proboscis 
long and slender, with small terminal lips; palpi very small and thin, in some examples blackish, in 
others pale rufous. Thorax, scutellum, and abdomen shining black ; humeral spots whitish. Abdomen 
conical; in the male the third and anal segments have a greyish tomentum and whitish lateral spots, and 
the anus is rounded, the latter having the genitals somewhat exserted beneath and turned towards the 
venter; in the female the grey tomentum and the whitish spots on the last two segments are absent, and 
the anus is pointed and armed with a small forceps; in both sexes the segments have long marginal 
macrochete. Legs black; middle and hind tibie with long bristles; foot-claws and pulvilli elongate in 
the male; the pulvilli yellowish. Tegule white. Wings hyaline, yellowish at the base; apical and 
posterior cross-veins oblique, the former nearly straight, the latter sometimes curved. 
