EPHYDRIDvE. 309 



27. Clypeus prominent 28 



Clypens hidden • . . 29 



28. The costal vein reaches to the third longitudinal vein (19, 20) . 



Brachydeutera. 

 The costal vein reaches to the tip of the fourth vein (24, 29) . 



Parydra. 



29. Claws almost straight; pulvilli indistinct (5). . Ephydra. 

 Claws curved; pulvilli distinct 30 



30. Oral border quite bare (33, 34). .... Ilythea. 

 Oral border bristly. 31 



31. Arista pubescent (32). Scatella. 



Arista pectinated. ........ Csenia. 



Ochthera humilis, enlarged. 



29 



