18 COSTA RICAN DIPTERA 



mouth margin slightly produced; eyes bare, almost round, Alesonotuni 

 without the post-humeral bristle and with 3 pairs of dorso-centrals, disk 

 with rather strong setulae, arranged in about 10 rows, the central pair be- 

 coming stronger as they recede; scutellum with 4 marginal bristles, the basal 

 pair slightly the weaker, disk bare, outline rounded, sterno-pleural bristle 

 of moderate strength. Legs normal, no ventral bristles on mid tibia, and 

 only the usual dorsal bristles present; basal joint of hind tarsus slightly 

 over half as long as second. Wing with costa ceasing at end of vein 3 and 

 distinctly before apex of wing, second costal division about If times as long 

 as third; second vein joining costa at an acute angle; basal section of vein 

 3 about one-third as long as last section of second and slightly longer than 

 section of fourth between the cross veins; outer cross vein almost directly 

 below middle of last section of second, and shorter than section of fourth 

 vein anterior to its junction with that vein; last section of third vein gradu- 

 ally inclining forward but not distinctly bent as in quadrisetosa; costa with 

 short setulose hairs to end of vein 1. Length, 1.5 mm. 



Holotype.— 9 , Cartago, May 25, 1909, in a ditch. Type No. 

 6028. 



Leptocera (Limosina) quadrisetosa new species 



Male. — In color rather darker than cartagensis. The face and cheeks 

 are yellow and contrast more with the other parts of the insect than in the 

 foregoing. The frons is not so noticeably pollinose and there is but little 

 contrast between the stripes which carry the setulae and the other parts 

 of frons. The wings are slightly grayish and the veins are more distinct, 

 especially the costal vein which is very thick and black. Halteres yellow. 



Frons with 2 orbital bristles, the lower slightly the smaller, both directed 

 outward; several weak hairs on orbits besides the bristles; central setulae 

 (3-4) distinct, decreasing in length anteriorly; face concave, mouth margin 

 produced; antennae of moderate size, third joint rounded, larger than 

 second; arista as in cartagensis; cheek slightly less than equal in height to 

 breadth of third joint of antennae, one-third as high at middle as height of 

 eye; marginal hairs rather numerous, in a double row, no central strong bris- 

 tles on cheek, vibrissa strong, incurved. Mesonotum with 2 pairs of dorso- 

 centrals; disk with numerous short setulae arranged in about 12 rows; 

 scutellum subtriangular in outline, disk bare, 4 marginal bristles present, 

 the basal pair slightly the weaker; disk slightly flattened. Abdomen cylin- 

 drical, shorter than thorax; hypopygium knob-like; the surfaces of all seg- 

 ments with numerous hairs. Legs rather stout; fore tarsi with the last 

 3 joints slightly flattened; mid tibiae with the usual dorsal bristles rather 

 weak, and one weak ventral bristle; hind tarsus with basal joint much di- 

 lated and over half as long as the less dilated second joint. Wings with 

 costa carried well beyond end of vein 3 but ceasing abruptly well before 

 wing tip, very thick from end of first vein and tapering from end of second 

 to its apex; second costal division slightly longer than third; angle at junc- 

 tion of vein 2 with costa obtuse; last section of vein 2 equal to2J- times tiie 



