296 DIPTERA. 
from it in the pale coloration of the face and cheeks, the more prominent front, the 
less approximate eyes (¢), the rufous antenne, the almost total absence of metallic 
gloss on the abdomen, and the absence of bristles on the facial ridges. This last- 
mentioned negative character is exceptional even in the genus Caldiphora, all the species 
of which, so far as I know, have the facial ridges more or less beset with bristles above 
the vibrisse. For the rest, the species is evidently congeneric with C. semiatra. 
CHLOROPROCTA, gen. nov.* 
Eyes bare. Front of the ¢ small, triangular (the eyes being quite coalescent), that of the 2 as broad as the 
eyes, somewhat narrower towards the root of the antenne ; frontal bristles weak ; orbital bristles absent 
in both sexes. Face perpendicular, the facial ridges convergent below ; vibrisse inserted a little above 
the oral margin; no bristles above them; cheeks with insignificant pilosity, their inferior portion equalling 
one-fourth of the longitudinal diameter of the eyes. Antenne inserted on the median line of the eyes ; 
basal joints short; third joint four times as long as the second and reaching the vibrisse ; arista plumose 
in its entire length, more densely on the upperside. Proboscis with well-developed terminal lips; palpi 
cylindrical, Thorax quadrate; dorso-central bristles inconspicuous, some posterior ones excepted ; 
scutellum semicircular, with marginal macrochete. Abdomen short-ovate, broader than the thorax, 
without macrochete, but with the last segments somewhat hairy. Legs slender, with weak bristles ; 
middle tibiz with a bristle on the inner side ; foot-claws and pulvilli short in both sexes. Tegule rather 
large. Wings longer than the abdomen; small cross-vein under the end of the first vein and on the 
middle of the discal cell; curvature of the fourth vein rectangular; apical cross-vein slightly concave ; 
apical cell opened nearly at the tip of the wing ; posterior cross-vein oblique and undulate, nearer to the 
curvature of the fourth vein than to the small cross-vein. 
The species for which this new genus is proposed are of about the size of our 
common house-fly, but they are broader and of a testaceous colour, with the last abdo- 
minal segments metallic-green. From Ochromyia, Macq., and Bengalia, Rob.-Desv., 
both including yellowish or rufous species, they differ in having the orbital bristles 
absent on the front in both sexes, and in the non-setulose third vein of the wings. 
1. Chloroprocta semiviridis, sp.n., ¢ @. (Tab. VII. fig. 16, 3.) 
Testaceous; thoracic dorsum blackish ; abdomen posteriorly metallic green ; antenne, palpi, and legs rufous ; 
wings brownish. 
Length 6 millim. 
Head yellowish-rufous; eyes of the g with large facets in the middle; beard yellow. Thoracic dorsum 
blackish-brown, with grey tomentum, which is most conspicuous on the front portion; pleure testaceous. 
Scutellum brown, slightly shining. First abdominal segment and the front margin of the second testa- 
ceous; the rest of the abdomen metallic bluish-green in the g, blacker and less metallic, save on the 
anal segment, in the 9. Legs rufous, the tarsi blackish towards the tip. Tegule yellow. Wings 
brownish, the colour more intense along the costa. 
Hab. Mexico, Northern Yucatan (Gaumer). 
Two specimens, one of each sex. 
2. Chloroprocta —— ? 
Hab. Mexico, Northern Yucatan (Gaumer). 
Two males and one female, all in a bad state of preservation. ‘They are undoubtedly 
* y\wpds (green) ; mpwkrds (rump). 
