186 



THE WINGS OF NEUROPTERA 



In Dilar nohirce and in Rexavins japonicns the radius of both fore and 

 hind wings bears two sectors. 



In all of these species the branches of the radial sector are so deeply- 

 forked that it seems probable that accessory veins are being interpolated. 



Marginal dashes are present. 



{k) THE WINGS OF THE BEROTHID.^ 



The type species of the Berothidag is Berotha insolita, the wings of which 

 are figured here (Fig. i8o). These wings present some striking features, 

 most of which, however, are foreshadowed in various genera of the hemero- 

 biid group of families. The wings of Berotha differ from those of the 

 hemerobiids in that the first radio-medial cross-vein of the hind wings is 

 transverse, not longitudinal and sigmoid, as it is in those families. 



trpnTTyri 



Fig. 1 80. — Wings of Berotha insolita. 



The most striking features of the wings of Berotha are the following: 

 the absence of a recur\^ed costal vein; the atrophy of the terminal portion 

 of the subcosta; the great reduction in the number of cross-veins, those of 

 the radial area being reduced to a single series of gradate veins; the fan- 

 like branching of the tips of veins; prominent marginal dots alternating 

 with the twiglike branches of the veins; the loss of vein Cuo of the hind 

 wings; the anastomosis of the first anal vein and vein Cui in the hind 

 wings; and, in the hind wings, the extending of vein Cui and the first 

 anal vein quite closely parallel with the inner margin of the wing, leaving 



