68 COSTA RICAN DIPTERA 



The species is alwa.ys recognized by the dark brown, opaque 

 upper, and contrasting gray lower surfaces, especially of the 

 head and thorax. The legs are pale. 



Only one specimen examined from Costa Rica: Over muddy 

 road, Peralta, March 24. 



EXPLANATION OF PLATE 



Fig. 1. — Notiphila erythrocera. Profile of head. X 20. 



Fig. 2. — Notiphila erythrocera. Middle tibia. X 20. 



Fig. 3. — Paralimna meridionalis. Profile of head. X 20. 



Fig. 4. — Paralimna ciliata. Fore femur of male. X 20. 



Fig. 5. — Hydrillia spinicornis. Profile of head. X 20. 



Fig. 6. — Allotrichoma abdominalis. Profile of head. X 30. 



Fig. 7. — Typopsilopa flavitarsis. Profile of head. X 25. 



Fig. 8. — Discocerina nitida. Profile of head. X 20. 



Fig. 9. — Atissiella setulosa. Profile of head. X 30. 



Fig. 10. — Gastrops nigra. Profile of head. X 20. 



Fig. 11. — Psilopa meridionalis. Profile of head. X 20. 



Fig. 12. — Plagiops nitidifrons. Profile of head. X 25. 



Fig. 13. — Ochtheroidea centralis. Profile of head. X 25. 



Fig. 14. — Ochtheroidea centralis. Fore femur of male. X 25. 



Fig. 15. — Nostima slossonae. Wing. X 25. 



Fig. 16. — Discocerina setulosa. Profile of head. X 20. 



Fig. 17. — Napaea nigripes. Profile of head. X 20. 



Fig. 18. — Lytogaster willistoni. Profile of head and abdomen. X 15. 



Fig. 19. — Ilythea flavipes. Profile of head. X 30. 



Fig. 20. — Ilythea flavipes. Wing. X 15. 



Fig. 21. — Ilythea fenestralis. Wing. X 15. 



Fig. 22. — Scatella stagnalis. Wing. X 15. 



Fig. 23. — Scatella nitidifrons. Wing. X 15. 



Fig. 24. — Brachijdeutera argentata. Profile of head. X 20. 



Fig. 25. — Ochthera humilis. Fore femur and tibia. X 20. 



Fig. 26. — Psilephydra nemorosa. Profile of head. X 25. 



Fig. 27. — Ephydra rostrata. Profile of head. X 20. 



Fig. 28-29. — Planinasus ambiguus. Head. X 25. 



