90 ELEMENTARY ENTOMOLOGY 



they may conveniently be considered together and termed "neu- 

 ropteroid insects." 



True Neuroptera. In the true Neuroptera the wings are usually 

 of equal size, with numerous cross veins, the mandibles are well 

 developed, and the metamorphosis is complete. The larvae -are 

 carnivorous, and the mandibles are usually long and pointed. One 

 of the best-known forms is the large hellgramite (Corydalus cor- 

 nuta), whose larvae, known as dobsons, are the favorite bait of 

 the bass fisherman. The larvae live under stones in swift-flowing 



FIG. 114. Cluster of eggs of the lace-winged fly (Chrysopii). (Greatly enlarged) 



(After S. J. Hunter) 



streams, where they feed on the young of various aquatic insects. 

 They are readily recognized by the leglike appendages and a large 

 tuft of tracheal gills on either side of each abdominal segment 

 (Fig. 113). It requires nearly three years for the larva to become 

 full grown, when it forms a cell beneath a stone, or some object 

 near the bank, and pupates, the adult appearing about a month 

 later. The adults are readily recognized, as they have a wing ex- 

 panse of from four to five and one half inches and the males have 

 remarkably long mandibles. On the rocks under which the larvae 

 live the eggs are laid in chalklike masses of from two to three 

 thousand. 



