DIPTERA. 363 



25. Psilopus interceptus, sp. n. 



J . Face blue, elongate, with white pollen : antennae black, small, second joint with a few small bristles only : 

 front pollinose below, with white hairs on the sides. Thorax green, very lightly pruinose with white, 

 the pleurae in a certain light white-pollinose ; halteres infuscated. Abdomen rather narrow at the base, 

 green, with black bands on the incisures ; hypopygium black, with round black lamellae and some small 

 filamentary organs. Coxae and trochanters, including the front ones, black : femora and tibiae yellow, 

 the latter with few bristles ; fore metatarsus one and a half times the length of its tibia, distinctly 

 whitish at the tip, the following four joints two-fifths the length of the preceding, black, the fourth 

 fringed above with black, the fifth with a shorter fringe of white ; middle tarsi infuscated from the base, 

 hind ones wholly black. Wings yellow in front at the base ; the cross-bands separated by a hyaline 

 space that runs forward to the second vein ; tip wholly infuscated, except behind. 



Length 7 millim. 



Hab. Mexico, Teapa in Tabasco (//. H. Smith). 

 One male. 



26. Psilopus pennifer, sp. n. 



cf . Face and front blue, deeply pollinose with white, a few pale hairs in a recumbent position at the corners 

 of the vertex ; antennae small, black, second joint with very few small bristles. Thorax brilliant blue, 

 verging into violet, the pleurae in the proper light bright white-pollinose. Halteres blackish. Abdomen 

 bright blue or green, with black bands including nearly half the width of the segments ; hypopygium 

 rather large, black, with rounded blackish lamellae, and two long feather-like appendages, which are 

 also blackish and covered with brown hairs. Coxae and trochanters black ; femora and tibiae yellow, the 

 hind femora at the tip and the hind tibiae at the base, however, infuscated for a fourth of their length ; 

 fore tibia with two minute bristles only, which are on the outer side ; fore metatarsus longer than the 

 tibia, with a few minute hairs on the underside, the tarsus infuscated from the tip of this joint ; middle 

 tibia with a few small bristles only, the tarsus like the front oue, but relatively shorter ; hind tibia rather 

 hairy, and provided with one noticeable bristle on the outer side near the base. Wings with the usual 

 two cross-bands, which are expanded both ways, so as to include almost the whole tip of the wing, and 

 also to make a costal stripe beginning before the end of the first vein; the intervening hyaline stripe 

 extends forward to the second vein. 



$ . Very like the male, but with the hind knees a little less infuscated. 



Length 5-2 millim. 



Hab. Mexico, Teapa in Tabasco (//. II. Smith). 



27. Psilopus flavicoxa, sp. n. 



Differs from P. pennifer in the following particulars only : — Fore coxae and trochanters yellow ; hind knees a 

 little less, but still perceptibly, infuscated ; halteres yellow or but slightly brownish ; hypopygium with 

 narrow yellow lamellae, and no feather-like processes. 



Hab. Mexico, Atoyac in Vera Cruz, Teapa in Tabasco (H. II. Smith). 

 Two males 



28. Psilopus clavipes, sp. n . 



<$ . Face and front metallic, overlaid in certain directions with white pollen, which is thinner on the latter ; 

 antennae small, black, with small and few bristles. Thorax bright green, pleurae white-pollinose. 

 Halteres pure yellow. Abdomen bright green, the last segment deep purple, the incisures with narrow 

 black bands ; hypopygium of moderate size, black, with rather large, black, hairy appendages. Middle 

 and hind coxae and their trochanters, and the hind tarsi, black. Fore coxae a little infuscated at the 

 base • fore tibia with a row of stiff bristles on the outer or hinder side. Fore tarsus with the first joint 

 almost as long as the tibia, blackened at the tip, with an irregular row of bristles on the outer side and 



3a 2 



