328 DIPTERA. 
After the most careful examination of the numerous female specimens before me, 
I am able to assign only a few of them to their respective males, sometimes on 
a mere conjecture; the majority of them must therefore remain undetermined for 
the present. 
1. Leucomelina pica. (Tab. VIII. figg. 8, ¢; 8a, head in profile, ¢ .) 
Leucomelina pica, Macq. Dipt. Exot., Suppl. 4, p. 262, t. 24. fig. 3°; Gigl-Tos, Mem. R. Accad. 
Scienze di Torino, ser. 2, xlv. (sep.) p. 18°. 
Eyes contiguous (¢); thorax black, with a white lateral band; anal segment cinereous, without distinct spot. 
Length 4:5-5 millim. . . 
Front triangular, black; the eyes contiguous; face and cheeks black, with white reflections ; the face shorter 
than the front, concave, slightly projecting ut the oral margin; inferior part of the cheeks linear, with a 
row of bristles. Antenne, proboscis, and palpi black; the antenne inserted on the median line of the 
eyes, the second joint with a minute bristle, the third joint two and one-half times as long as the second ; 
arista slightly pubescent. ‘Thorax deep black; a broad band on each side, extending from the shoulder 
to the root of the wings, and’some spots on the pleure, above the coxee, white; in the hind angles before 
the scutellum are two large whitish reflecting spots; scutellum trigonal, black, with a cinereous hind 
border; metanotum grey. Abdomen conical, truncated at the apex, cinereous; first segment, except at 
the sides, with a narrow hind margin and the beginning of a dorsal line, black ; second segment with two 
large black spots, which do not quite reach the hind border, and are placed so close together that there 
remains only a narrow dorsal stripe of the ground-colour between them (these spots usually appearing 
trigonal, but sometimes they are more quadrangular in shape); third segment with two similar spots, 
which are usually a little smaller than those on the second segment, and sometimes assume the form of a 
short transverse band immediately before the hind margin of the segment, this being extended on the 
inner side in a longitudinal projection, along which the dorsal stripe of the preceding segment is prolonged ; 
anal segment unicolorous cinereous, more or less infuscate in the middle; many macrochete and bristly 
hairs are present on the sides and towards the end of the abdomen. Legs black, slender; front femora 
with a row of regular bristles on the upper and under sides; foot-claws and pulvilli elongate, the pulvilli 
white. Tegule yellowish-grey; halteres yellow. Wings brownish-hyaline; small cross-vein under the 
end of the first vein and beyond the middle of the discal cell; terminal section of the fourth vein distinctly 
curved upwards in the middle; posterior cross-vein oblique and nearly straight. 
Hab. Mexico 2, Orizaba (H. H. Smith and F. D. Godman), Xucumanatlan 7000 feet 
and Omilteme 8000 feet, both in Guerrero (H. H. Smith).—Braziu'. 
Four male specimens. | 
2. Leucomelina corvina. 
Leucomelina corvina, GiglTos, Mem. R. Accad. Scienze di Torino, ser. 2, xlv. (sep.) p. 19°. 
Eyes contiguous (¢); thorax black, with a lateral band, and two stripes before the transverse suture, white ; 
anal segment with a brown dorsal stripe. 
Long. 4-5 millim. 
Differs from the preceding (L. pica) in the greater extension of the white markings on the thorax ; the lateral 
band is broader; the transverse suture has a white margin, which is interrupted in the middle, and on 
the prothorax are two white longitudinal stripes, joining the interrupted end of the white margin at the 
suture; the whitish spots at the posterior angles of the thorax are larger; the scutellum is cinereous, and 
black at the base only. The abdomen agrees in coloration and markings with that of L. pica, except that 
the black spots are often smaller and the dorsal stripe broader; the anal segment has in the middle a 
distinct brown or blackish stripe. The wings are clearer; the curvature of the terminal section of the 
