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Annals Entomological Society of America [Vol. VI, 



these cells undergo. In fact a condition like that shown in 

 Fig. 6 (Smicridea sp.) suggests that the corneous point submits 

 to annihilation in preference to displacement. 



Fig. 5. a, Apical venation of fore wing of Leptocerus sp. cf. 

 b, Hind wing of same, c, Fore wing of female of same. 



If then we give any weight to the comparison with Heli- 

 copsyche and the Molannidas and to the position of the corneous 

 points we should conclude that in the Leptoceridee also R5 has 

 arched into Mi-^o its distal end fusing with the latter compound 

 vein and that what appears to be the cross vein rm is in reality 

 the base of R5. 



Fig. 6. Radial sector in the fore wing of Smicridea divisa. 



In almost all of the Leptoceridse media is reduced to two 

 branches but in the subfamily Triplectidinae and in females of 

 the genus Leptocerus a more generalized condition obtains, 

 that is, media is apparently three branched (Fig. 5c). If the 

 view here advocated is correct these generalized Leptoceridae 

 are in exactly the same condition as regards the relation of R5 

 and media as is Helicopsyche, that is, R5 has arched into Mi+.. 

 but has not fused with it distally. There is of course the other 

 possibility that it is Mi and Mo that are separate and R5 and Mi 



