148 C. H. TYLER TOAVNSEND. 



16. — Fourth vein forked almost immediately below small cross-veiu. the prte- 



furca, therefore, very short I^asiosoma. 



Fourth vein forked far beyond small cross-vein, the prsefurca long 17. 



17. — Fifth vein forked exactly opposite, or before small cross-vein ; third vein 



always straight Neoenipheria. 



Fifth vein foi'ked far beyond small cross-vein ; third vein sometimes 



sinuate Polylepta. 



18. — Three ocelli present-- 19. 



Only two ocelli Mycetophila. 



19. — Costal vein extending more or less beyond extremity of third vein 20. 



Costal vein reaching only to extremity of third vein 28. 



20.— Fifth vein not furcate Acneinia. 



Fifth vein furcate 21. 



21. — Fork of fifth vein lying before or under fork of fourth..^ 22. 



Fork of fifth vein lying perceptil)ly beyond the fork of the fourth. 



Phthiiiia. 



22. — Proboscis elongate, beak-like Oiioriste. 



Proboscis not elongate 23. 



23. — Front branch of first vein (auxiliary) connected with main branch by a 



cross- vein 24. 



Front branch of first vein not connected with main l)ranch by a cross-vein. .26. 

 24.— Ocelli of nearly equal size; front branch of first vein broken ofl' and ter- 

 minating in the cross-vein which connects it. with the main branch. 



Sy lit emu a. 

 Ocelli of unequal size; front branch of first vein nowhere broken off. but 



terminating in front margin 25. 



25. — Costal-vein extending widely beyond termination of third vein..Boletiiia. 

 Costal vein extending but little beyond termination of third ; ai^tenuse like 



Platyura Dioniouus. 



26. — Second basal cell very long, reaching beyond middle of wing; bases of 



upper branches of fourth and fifth veins indistinct L<eia. 



Second basal cell moderately long, always ending before middle of wing; 



bases of upper branches of fourth and fifth veins distinct 27. 



27. — Fourth posterior cell lying between the two branches of fifth longitudinal 

 vein, very pointed or acute at base and generally very narrow, the 



branches only a little divergent Kpicypta. 



Fourth posterior cell moderately wide, branches of fifth vein strongly diver- 

 gent Docosia. 



28.— Fifth vein furcate 29. 



Fifth vein not furcate Zygoniyia. 



29. — Front branch of lirst vein very long, and always ending in costa. 



IVeoglapliyroptera. 

 Front branch of first vein very short, or if longer, then always ending in 



main branch, not in front border 30. 



30. — Fifth vein forked before^or opposite small cross-veiu, and always nearer to 



base of wing than to fork of fourth 31. 



Fifth vein forked beyond small cross-vein, and always nearer to wing bor- 

 der than to fork of fourth Mycotliera. 



* Walker does not mention ocelli in description of Diomonns, which is here 

 included. 



