CHAPTER XVI. 

 NEUROPTERA. 



In the order as first established by Linnaeus, were in- 

 cluded the May flies, the dragon flies, the caddis flies, and 

 some other insects to be mentioned later. At present, the 

 May flies, with their flat, external abdominal gills, form 

 the order of the Ephemerida; the stone flies, with their 

 filamentous, thoracic gills, their ocelli as well as compound 

 eyes, and their inability to live in stagnant water, form 

 the order Plecoptera; the dragon flies, with their internal 

 rectal gills in the larval stage, their peculiar aerating 

 system, and their strong adult wings, form the order 

 Odonata; the caddis flies, or caddis worms, after their 

 more familiar larval appearance, form the order Trichop- 

 tera; while the lace- winged flies, the dobsons, the ant lions, 

 and the scorpion flies are left to make up the order 

 Neuroptera. 



All the insects of the order have net- veined wings, 

 strong mouth parts, either for biting or piercing, and a 

 development by complete metamorphosis. So far as 

 known, the members of the order are carnivorous in their 

 feeding habits, and many of them are aquatic in the larval 

 stage. The snake flies, rather rare insects with the pro- 

 thorax slender and curved, making them look humpbacked, 

 feed largely upon the larvae of the codling moth, one of our 

 worst apple-tree pests. The aphis lion, in its larval stage, 

 crawls about over the surface of plants infested with plant 

 lice and makes short work of them. Later in the summer, 



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