26 COSTA RICAN DIPTERA 



the width of frons; palpi small, moderately bristled; vertex not raised; ocel- 

 lar region not raised. Mesonotum with 1 pair of dorso-centrals; scutellum 

 very small, with 2 long marginal bristles. Hypopygium exserted, of moder- 

 ate size; anal protuberance but slightly protruding, hairy. Legs rather 

 thick; fore tarsi thickened distinctly, the basal joint noticeably so; hind 

 femora much thickened; fore tibia without bristles; mid tibia with the 

 usual 2 at basal third, which are rather weak; hind tibia with 1 at middle 

 on antero-dorsal surface. (These are all the bristles I can detect on the type, 

 but the legs are in awkward positions for examination.) Costa to middle 

 of wing, first division of costa slightly longer than second, fringe short, 

 about equal in length to diameter of costal vein; third vein thickened, 

 distinctly broader than costal vein; fourth vein gently arcuated, ending 

 at a little before wing tip; veins 6-7 indistinct at apices. Length, 1.25 mm. 



Holotype.—Ala'iuela, September L5, 1909, 3100 feet altitude, 

 by sweeping. Type No. 6038. 



Apocephalus curvinervis new species (Fig. 1.) 



Female.— Yellow, slightly shining. Frons brown, paler anteriorly. An- 

 tennae, proboscis, and palpi yellow. Abdomen with basal two-thirds of 

 each segment dull black, apical third of each segment yellow; ovipositor 

 brown-black, shining. Legs entirely yellow. Wings clear, costa browned 

 beyond apex of third vein; veins brown, 4 and 5 slightly infuscated. Hal- 

 teres yellow, knobs black. 



Frons slightly longer than broad; vertical row of bristles normal, pre- 

 ocellar row with the two center bristles in transverse line with lower mar- 

 gin of anterior ocellus, the outer pair close to eye margin and distinctly 

 lower on frons; front row consisting of two large, divergent, post-antennal 

 bristles which are not very closely approximated, and an outer pair close 

 to eye margins distinctly above the level of these ; surfaces of frons with 

 numerous short setulae; ocelli very well developed; antennae of moderate 

 size, third joint pear shaped, its apex not extending beyond the level of 

 base of post-antennal bristles; arista bare, basal joints swollen and dis- 

 tinct, total length of arista equal to that of frons; proboscis small; palpi 

 small with very few bristles; eye facets becoming larger as they near lower 

 margin. Pleura bare; scutellum in type without any bristles, nor can I 

 trace any marks that would indicate that there have been any present, 

 though normally I should expect that there should be 2. Abdomen elongate, 

 th(> ovipositor slightly longer than high, knife-shaped, the upper surface at 

 apex with 2 small knob-like protuberances which have a few hairs on their 

 surfaces. Legs elongate; hind femora with 3-4 bristly hairs on their basal 

 fourth; hind tibial setulae very short, but distinct. Wing venation as in 

 figure 1 ; fourth vein leaving at slightly beyond fork of third and bent down- 

 ward at apex; costal fringe very short. Length, 2.5 mm. 



Holotijpe. —Ahijnelsi, September 15, 1909, .sw(>pt at 3100 feet 

 altitude. Type No. 6039. 



