188 



THE WINGS OF NEUROPTERA 



In these wings the development of definitive accessory veins on the 

 radial sector and the regularity of the border of marginal accessory veins 

 have reached a very high degree of perfection. 



Cu- 



Fig. 1 8 1. —Wings of Polystcechotes ptinctatns. 



(m) THE WINGS OF THE PSYCHOPSID^ 



Among the remarkable types of wings that have been developed in the 

 Neuroptera that of the Psychopsidas is one of the most striking. I have 

 selected as an illustration of this type the wings of an undetennined 

 psychopsid from West China (Fig. 182), as in this species the venation of 

 the wings is not obscured by blotches of color as it is in the only species of 

 Psychopsis in our collection. 



The more striking features of these wings are their rounded form; the 

 unusual width of the costal area throughout its length; a peculiar nexus of 

 the tips of veins Sc, Ri, and Rg; the presence of two series of gradate veins; 

 the irregular distribution of the radial cross-veins in both wings and of the 

 cross-veins in the svibcostal area of the fore wings; and the unusual length 

 of the stalk of media, especially in the hind wings. 



The branches of the radial sector are very regular except that one in the 

 fore wing, the sixth, is split nearly to its base, indicating that an accessory 

 vein is being interpolated. 



Nearly all of the veins are forked at the tip; and marginal dots are 

 present. 



