EXORISTA. | 65 
laterally with some white tomentum; thoracic dorsum before the transverse suture with four black lines, 
which are sometimes obsolete ; scutellum rufous. Abdomen broadly ovate, blackish, with irregular whitish 
or greyish reflecting spots, densely beset with bristly hairs and having discal and marginal macrochete ; 
anal segment laterally slightly rufous. Legs black, the tibiz piceous ; hind tibia outwardly with bristles 
of unequal length. Tegule whitish. Wings greyish-hyaline; small cross-vein before the middle of the 
discal cell ; apical and posterior cross-veins slightly curved, nearly straight. 
Hab. Mexico, Amula in Guerrero 6000 feet (H. H. Smith). 
A single female specimen. 
7. Kxorista elongata, sp.n, ¢. (Tab. III. figg. 8, 8a, head in profile, ¢ .) 
Oblong, black ; head pale yellow; palpi dark rufous ; thorax cinereous, with four black stripes; abdomen with 
the front margins of the segments white, and with discal and marginal macrochete ; base and costa of 
the wings infuscated. 
Length 10 millim. 
Front narrowed behind; frontal band black; frontal bristles rather stout, descending on both sides in a curved 
row as far as the end of the second antennal joint; vibrissee surmounted by several shorter bristles; beard 
yellowish-grey. Eyes pubescent. Antenne black; second joint short ; third joint three or four times as 
long as the second ; arista thickened to one third of its length. Thorax greyish-cinereous, with four 
black stripes, the outer stripes prolonged behind the transverse suture; pleure whitish-grey ; scutellum 
black, with the hind margin grey. Abdomen elongate-conical ; first segment black, if anything shorter 
than either of the following segments, which are black with grey reflections and a white front margin, 
the second segment at the sides slightly testaceous ; macrochete long and abundant, on the second and 
following segments in the middle and on the hind margins. Legs black, long and slender, with stout 
bristles, especially on the middle tibie ; foot-claws and pulvilli elongate. Tegule cinereous, with a pale 
yellow margin. Wings greyish, somewhat infuscated at the base and along the costa; curvation of the 
fourth vein forming a blunt angle; apical cross-vein straight ; posterior cross-vein a little curved, inserted 
on two-thirds of the apical cell. 
Hab. Costa Rica, Cache (Rogers). 
A single male specimen. 
Two other male specimens, from Medellin near Vera Cruz (HZ. H. Smith), are of a 
smaller size, and without the infuscation on the wings; they probably belong to a 
variety of the same species. 
In the elongate shape of the body and legs L. elongata resembles some species of 
Macquartia ; but, owing to the third antennal joint being much longer than the second, 
the end of the apical cell more removed from the wing’s tip, and the broader front (in 
the male), it is better placed in the genus Frorista. 
8. Exorista hispida, sp. n., ¢ ¢. 
Black, setose ; head pale ochraceous; third antennal joint more or less rufous; thorax somewhat greyish ; 
abdomen with white and grey reflecting spots, and with discal and marginal macrochete ; palpi pale 
rufous. 
Length 7 millim. 
Front narrowed behind, on the vertex half as broad as the diameter of the eyes (¢ ), or a little narrower than 
the eyes (Q); frontal band black ; frontal bristles robust, descending on both sides to the number of three 
or four beneath the root of the antenne ; vibrisse rather strong, accompanied by several shorter bristles ; 
pilosity of the eyes pale ochraceous or whitish, long and dense. Antenne a little shorter than the face ; 
basal joints short, black ; second joint bristly ; third joint four times as long as the second, rather broad 
BIOL. CENTR.-AMER., Dipt., Vol. II., February 1890. k 
