40 DURHAM DIPTERA. 



III. 



56 (45). Base of the fork of V.5. distinctly beyond the base of 



the fork of V.4. 



57 (58). V.I. a. as long or nearly as long as 0.4 1 . 



41. Ccelosia, Winn. 



58 (57). V.I. a. very short and scarcely the eighth of the length 



of 0.4 1 . 



59 (60). Costa reaching far beyond the end of V.3. 



35. Anatella, Winn. 



60 (59). Costa reaching very little beyond the end of V.3. 



36. Phronia, Winn. 



61 (40). Costa reaching only to the end of V.3. 



62 (65). V.5. not forked. 



63 (64). V.3, close to V.I., curved, and running nearly parallel 



with the costa. 37. Sceptonia, Winn. 



64 (63). V.3. rather distant from V.I., and not parallel with 



the costa. 38. Zygomyia, Winn. 



65 (62). V.5. forked. 



66 (67). V.I. a. very long, and always ending in the costa. 



43. Glaphyroptera, Winn. 



67 (66). V.I ,a, very short, or if longer then always ending in 



V.l.b., and not in the costa. 



68 (75). V.5. forking before or under X.4., and always nearer 



to the root of the wing than the base of the fork of 

 V.4. 



69 (70). V.I .a. reaching beyond the middle of 0.4 1 . 



28. Trichonta, Winn. 

 70(69). V.I. a. never reaching to the middle of 0.4 1 , often 



rudimentary. 

 71 (72). Base of 0.5.b. very acute; V.5.b. from its middle 

 suddenly diverging from V.5.a. 



29. Rhymosia, Winn. 

 72(71). Base of 0.5.b. not very acute; V.5.b. diverging 

 gradually. 



73 (74). V.7, short but distinct. 31. Allodia, Winn. 



74 (73). V.7. entirely wanting. 33. Brachycampta, Winn. 



75 (68). V.5. forking beyond X.4., and always nearer the 



margin of the wing than the base of the fork of V.4. 



