EXORISTA. 63 
2, Exorista unicolor, sp. n., ¢. 
Shining black ; thorax without stripes; head with silvery reflections; abdomen with some grey tomentum ; 
macrocheetee very short ; palpi rufous. 
Length 7 millim. 
Head obscure, with silvery-white reflections ; front narrowed behind, on the vertex as broad as the diameter 
of the eyes ; frontal band black; frontal bristles descending on both sides in a curved row to beneath the 
second antennal joint ; above the vibrisse a row of shorter bristles, which mount up to nearly half of the 
face. Eyes pubescent. Antenne black, a little shorter than the face ; second joint bristly ; third joint 
four times as long as the second; arista thickened on the proximal half. Proboscis black ; palpi rufous, 
with short black hairs. Thorax and scutellum unicolorous shining black. Abdomen broadly ovate, 
shining black, with a slight whitish or greyish tomentum on the front border of the second and third 
segments, in which appears a black dorsal line; discal and marginal macrochete present, but very short 
and less conspicuous among the black pile which covers the abdomen. Legs black; the front and the 
hind tibie outwardly with a row of bristles; middle tibize with some longer bristles; foot-claws and 
pulvilli short. Tegule yellowish-grey. Wings hyaline ; small cross-vein on the middle of the discal cell ; 
apical and posterior cross-veins oblique and nearly straight, the latter inserted at or just beyond the 
middle between the small cross-vein and the curvation of the fourth vein. 
Hab. Mexico, Cuernavaca in Morelos, Venta de Zopilote 2800 feet, and Amula 
6000 feet, in Guerrero (H. H. Smith), Santiago Iscuintla in Jalisco (Schumann). 
Several female specimens. 
3. Exorista ochracea, sp. n., 3 ¢. 
Ochraceous; frontal band, antenne, hind borders of the abdominal segments, and legs black; thorax with 
black lines ; abdomen with discal and marginal macrochete ; palpi rufous. 
Length 5:5-7 millim. 
Front ochraceous with brownish reflections, nearly as broad as the diameter of the eyes, in the male narrower 
behind; frontal bristles descending on both sides in a single curved row beneath the root of the antenne ; 
face whitish; vibrissze surmounted by some shorter bristles. Eyes thinly pilose, in the female sometimes 
only slightly pubescent. Antenne shorter than the face ; third joint four times as long as the second; 
arista thickened to nearly half its length. Proboscis black; palpi pale rufous, exserted. Thorax and 
scutellum bright ochraceous; thoracic dorsum with four black lines, the outer lines largely interrupted 
on the transverse suture, and the inner ones not prolonged behind it; pleure greyish. Abdomen broadly 
ovate, ochraceous, with brown reflections; the first segment and a narrow hind border to the following 
two segments black. Middle tibie with some long bristles; foot-claws and pulvilli elongate in the 
male; the pulvilli pale yellow. Tegule yellowish. Wings greyish-hyaline; small cross-vein a little 
before the middle of the discal cell; apical cross-veia slightly concave or nearly straight (the apical cell 
ending at a short distance from the wing’s tip); posterior cross-vein curved. 
Hab. Mexico, Amula 6000 feet, Xucumanatlan 7000 feet, and Omilteme 80U0 
feet, in Guerrero, Atoyac in Vera Cruz, Teapa in Tabasco (H. H. Smith) ; Costa Rica, 
Rio Sucio (Rogers). 
Several specimens of both sexes. 
E. ochracea bears a striking resemblance to Mystacella fuscicostalis (p. 57); but 
differs in having the vibrisse inserted quite at the oral margin, the costa of the wings 
not infuscated, and the stripes on the thorax more linear. Mr. Smith has noted that 
living specimens are sometimes marked with golden-green and have the scutellum 
bronze. Some indications of this coloration are visible in dried examples, 
