40 | DIPTERA. _- 
2, Gonia mexicana, sp. n.,g 9. (Tab. WV. figg. 19,6; 194, head; 196, hind 
leg; 20,9; 20a, head.) | 
Head pale rufous, with cinereous tomentum ; thorax black ; scutellum testaceous ; abdomen in the male rufous, 
with a black dorsal stripe, in the female black, with two large lateral rufous spots; antenne and legs 
black ; tegule whitish; wings nearly hyaline, pale rufous at the base. 
Length 11-12 millim. 
In general appearance agreeing with the European G. divisa, Meig. The head of a paler colour and having 
more cinereous reflections, between which a clear ferruginous frontal band is more perceptible. Antenne 
black, the basal joints, however, being more or less rufous; in the male the third joint is four to five, in 
the female two or three, times as long as the second; the penultimate and terminal joints of the arista are 
of equal length. The cinereous tomentum on the thorax is not dense enough to alter the black ground- 
colour; of longitudinal stripes only faint traces are to be seen; the hind borders of the thorax, and in the 
male also the shoulders and the sides, are somewhat rufous. Abdomen ovate; in the male a little 
elongate, reddish-yellow, with a narrow dorsal black stripe, which is somewhat interrupted at the 
incisions, these having a whitish reflection; in the female black, with two large lateral rufous spots, 
the spots occupying the hind ‘portion of the first segment, the whole of the second segment, and the 
front border of the third segment in such a manner that a dorsal band is formed. Macrochete of the 
second and third segments only at the hind margin. Legs black; the front and hind tibis on the outside 
fringed with short bristles, the latter also with some longer bristles in the middle and at the end; the 
outer bristles of the middle tibiz long and stout. 
Hab. Mexico, Ciudad in Durango 8100 feet (forrer). 
Two specimens, a male and a female. 
GYMNOCH ATA. 
Gymnocheta, Robineau-Desvoidy, Essai sur les Myodaires, p. 371 (1880). 
1. Gymnocheta reinwardti. 
Tachina reinwardtii, Wiedem. Aussereur. zweifl. Ins. ii. p. 315. 62°. 
Had. Guatemata, Lanquin in Vera Paz (Champion).—Braziu!. 
A single male specimen, agreeing in its principal characters with Wiedemann’s 
description!, "Wiedemann calls the face, the occiput, and the orbits of the eyes 
“ snow-white,” the oral margin “ ferruginous,” and the front “black.” In the Guate- 
malan specimen the head is not so purely white, and beneath (as also at the oral 
margin) inclines to yellow; at the sides of the front the metallic green ground-colour 
shines through the greyish-black tomentum; the median band is narrow, especially 
posteriorly, black, but just above the antenne slightly testaceous; frontal bristles 
abundant, descending on both sides in a single row, to the number of five or six 
beneath the root of the antenne. Hyes densely clothed with greyish-yellow pile. 
Macrochete in the middle as well as on the hind margin of the second and third 
abdominal segments. Legs black; the front femora outwardly with white tomentum 
(Wiedemann calls the femora “dark green”). Wings without a costal spine; fourth 
vein not prolonged at its point of curvature; small cross-vein placed a little before the 
middle of the discal cell; posterior cross-vein faintly curved. 
