NEUROPTERA 



69 



resembles the male, except that the mandibles are comparatively short. 

 The larva? are called dobsons or hellgrammites by anglers and are used by 

 them for bait, especially for bass. Figure 112 represents a full-grown 

 dobson, natural size. These larvae live under stones in the beds of 

 streams. They are most abundant where the water flows swiftest. They 

 are carnivorous, feeding upon the nymphs of stoneflies, mayflies, and 

 other insects. When about two years and eleven months old, the larva 

 leaves the water, and makes a cell under a stone or some other object on 

 or near the bank of the stream. This occurs during the early part of 

 the summer; here the larva changes to a pupa. In about a month after 

 the larva leaves the water the adult insect appears. The eggs are then soon 

 laid; these are attached to stones or other objects overhanging the water. 

 They are laid in blotch-like masses, which are chalky-white in color, and 

 measure from half an inch to nearly an inch in diameter. A single mass 

 contains from two thousand to three thousand eggs. When the larvae 

 hatch they at once find their way into the water, where they remain until 

 full-grown. 



There are other common species of the family which closely resemble 

 Corydalus but are smaller, the larger ones measuring less than two and a 

 half inches in length, and having a wing- expanse of not more than four 

 inches. 



The comb-horned fish-fly Chaidiodes pectinicomis, has serrate antennae 

 and grayish wings while a closely related fish-fly, Nigronia serricornis, 

 also with serrate antennae, has darker, more brownish wings, spotted with 

 white dots. 



Family Chrysopid^e 

 The Lacewing-flies or Aphis-lions 



The family Chrysopidae includes the insects commonly known as 

 lacewing-flies; these and their larvae, the aphis-lions, are common and 

 well-known insects; they are found upon herbage and the foliage of 

 shrubs and trees throughout the 

 summer months (Fig. 113). 



The adults are easily recog- 

 nized by their delicate lace-like 

 wings (Fig. 114) and their green 

 or yellowish-green color. Their 

 eyes are large and shine like 

 molten gold when alive. They 

 are often called golden-eyed flies; 

 and because some of them when 

 handled emit a disagreeable odor 

 they have been called stink-flies, 

 an undesirable name for such 

 beautiful insects. 



The larvae of the lacewing- 

 flies are known as aphis-lions, 

 because they feed upon aphids; 

 they are found on the foliage of 



