12 COSTA RICAN DIPTERA 



2 orbital bristles present; one on about middle which is directed slightly 

 outward over the eye and the other almost in line with the posterior ocelli 

 and directed slightly inward and backward; the normal central setulae 

 represented in type by only 1 or 2 pairs near to anterior margin ; antennae 

 of moderate size, divergent but not lying very close to the eye; third joint 

 barely larger than second, pilose, arista hair-like, slightly pubescent, genic- 

 ulated at junction of second and third sections; cheek about one-half as high 

 as eye; eye distinctly longer than high; vibrissae distinct, cheek bristles 

 weak. Mesonotum with the normal pair of dorso-central bristles on pos- 

 terior fourth, and a much stronger pair situated on the lateral pale stripes 

 at about middle of mesonotum; discal setulae distinct, acrostichals arranged 

 along margins of the central stripe; scutellum large, its length about equal 

 to one-half that of the mesonotum, rounded in outline, four marginal bris- 

 tles present, the basal pair much weaker than the apical pair, disk bare. 

 Hypopygium large, knob-like; surface of abdomen with sparse hairs. Legs 

 with short surface hairs; mid tibiae with 4 to 5 dorsal bristles, the two at 

 apical third most distinct. Wing venation as in figure 8. There is a dis- 

 tinct fold which extends from before middle of discal cell to well beyond 

 outer cross vein; costa with hairs but not spinose. Length, .75 mm. 



Holotype. — Juan Vifias, May 3, 1910, near brook, forest edge, 

 2500 feet altitude. Type No. 6020. 



Leptocera (Limosina) vittata new species (Fig. 7.) 



Male. — ^Black, slightly shining. Frons yellow, ocellar spot blackened, 

 orbits, a central stripe and margins of frontal triangle whitish poUinose; 

 face yellow, cheeks blackened; antennae yellow; third joint darkened above. 

 Mesonotum black-brown, with grayish pollinosity and 3 brown vittae, the 

 outer one of which is broadest; scutellum concolorous with the mesono- 

 tum, with a subdistinct central pollinose stripe. Abdomen glossy black. 

 Legs yellow, coxae blackened, all femora browned at bases; fore tibia with 

 a narrow preapical blackish ring, mid and hind tibiae with two black bands, 

 one near base and the other near to apex; apices of tarsi darkened. Wings 

 spotted much as in poeciloptera but differing as shown in figure 7. Halteres 

 black, stalk yellow. 



Frons slightly over one-half the head width, becoming broader at just 

 above the level of antennae, where there is a slight emargination of the ej'e; 

 lower orbital bristle above middle of orbit, below it there are some weak 

 orbital hairs; central setulae absent; cheek short; vibrissa and some mar- 

 ginal hairs distinct; eye about four times as high as cheek and very distinctly 

 higher than long; antennae of moderate size; third joint pilose; arista gcnic- 

 ulated, slightly pubescent. Mesonotum with one pair of dorso-central 

 bristles, the anterior large pair in poeciloptera not distinguishable in this 

 specimen (though it is not in very good condition) ; scutellum with 4 sub- 

 equal marginal bristles, disk bare. Hypopygium large and knob-like, the 

 ventral organ projecting claw-like; dorsum of abdomen with scattered hairs, 

 hypopygium with L2 long hairs on left side at apex and scattered surface 



