CHAPTER VIII 



THE DRAGON FLIES, DAMSEL FLIES, MAY FLIES, 

 STONE FLIES AND CADDIS FLIES 



All of the insects described in this chapter spend their 

 early or larval life in the water, and the adult insects 

 are frequently seen near the water, although they may 

 at times fly to a great distance from it. The dragon flies 

 have four wings of similar shape and nearly equal size, 

 which are held out horizontally when the insect is at rest. 

 They have strong biting mouth parts and enormous com- 

 pound eyes which cover over a large part of the surface 

 of the head and enable the insect to see in almost all 

 directions at once. Vision in the dragon flies is very acute, 

 as it must be to enable them to catch the small flying 

 insects which furnish their food. Their powers of flight 

 are developed in proportion to their keenness of vision. 

 Watch a dragon fly darting through the air in the hunt 

 for prey, or better still attempt to catch one in a net, and 

 you will appreciate the efficiency of its eyes and wings. 

 Although dragon flies are called " snake feeders," "devil's 

 darning needles," and other uncomplimentary names, and 

 are associated, like the praying mantis, with a lot of foolish 

 superstitions, they are entirely harmless, and indeed very 

 useful creatures, since they devour many other insects, 

 including a considerable number of mosquitoes. The 

 eggs of dragon flies are laid in the water, and hatch out 

 into dull-colored, inconspicuous, slow-moving larvae, which 

 prowl along the bottom after prey or lie in wait for it to 

 come near. The larva is furnished with a peculiar 



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