208 THE WINGS OF NEUROPTERA 



' (t) THE WINGS OF THE NEMOPTERID^ 



The members of the Nemopteridse are most beautiful insects which 

 present a striking appearance on account of the distinctly characteristic 

 form of their hind wings. These are exceedingly long and narrow, ribbon- 

 like or thread-like; sometimes they are enlarged before the extremity; in 

 this case the narrow part is termed the petiole and the enlarged part the 

 spatula. 



The fore wings are triangular in outline (Fig. 206) and are furnished 

 with many cross-veins. In the more general features of their venation 

 they show striking resemblances to the wings of the myrmeleonids. 



The subcosta and vein Ri coalesce near the apex of the wing ; the sub- 

 costal cell is free fromi cross-veins; the radial sector is pectinately branched; 



Fig. 206. — Fore wing of Nemoptera sinuata; 0, oblique vein, 

 vein M3+4. 



the media is of the same type as in the Myrmeleonids and Ascalaphidas, 

 vein M3+4 coalescing with vein Cui, and the basal part of vein M3+4 

 appearing like an oblique cross- vein. The position of this oblique vein 

 varies greatly; in Nemoptera (Fig. 206) and in Oliverina (Fig. 207) it is 

 near the base of the wing; in Croce (Fig. 208) it is beyond the secondary 

 cubital fork. 



Vein Cui & M3+4 is pectinately branched, and the first accessory vein 

 is usually stouter than the others, forming a secondary cubital fork. 



Vein Cu2 is not reduced in Nemoptera (Fig. 206) and in Oliverina (Fig. 

 207) ; but in Croce (Fig. 208), it coalesces with the first anal vein, the basal 

 part of vein Cuo being reduced to the condition of a very stout oblique 

 cross- vein. 



In the hind wings the venation is somewhat reduced, as would be 

 expected, owing to their extremely narrow form. The maximum number 

 of longitudinal veins is found in Nemoptera and in Oliverina; in these 

 genera they are five in number. 



