192 



THE AMERICAN NATURALIST 



[Vol. LVI 



expansion approached completion, a regular system of blood- 

 veins in the spaces between the permanent veins. These show 

 plainly only in the few minutes when the wing has become 

 partially transparent, but in the adult wing they produce a 

 characteristic waviness of the membrane, and a few of them may 

 be seen in a favorable light as faint white lines. The arrange- 

 ment is perfectly definite : the narrow cells are filled by a series 

 of simple, evenly spaced, cross-veins, while in cells R, 1st M, and 

 ai they form a double series of cells alternating with each other. 

 On the narrow margin beyond the ambient vein they are evenly 

 spaced, the regular longitudinal veins each ending opposite the 

 middle of a marginal cell. Toward the costa there are two veins 

 opposite each definitive cell, while opposite cells M3 and M4 

 there are three, and opposite cell Cu^ there appear to be four. 

 The margin of the hind wing is similar, but the disc of the wing 

 was not observed. In the large triangular anal cell (3d Aj), 

 instead of cross-veins there is a series of closely spaced parallel 

 longitudinal veins, which remain visible in the dried wing. 



It seems possible that these structures are the relic of a net- 

 veining such as occurs in the Neuroptera. The different arrange- 

 ment in the anal region is especially suggestive, as it would 

 correspond to the plaited portion of the wing in the Orthoptera, 

 where there exist numerous parallel longitudinal veins. 



The figure is drawn from memory so far as the fugitive veins 

 are concerned, checked up by the few that could be traced in 

 the dry wing; it can be trusted only approximately. 



Wm. T. M. Forres 



Cornell University, 

 Ithaca, New York 



