50 ■ THE SIX-FOOTED INSECTS 



Order 14. Mecoptera; Scorpion flies. Two pairs of narrow, 

 membranous wings or none. Larvae caterpillar-like. 



Order 15. Trichoptem; Caddis flies. Hind wings usually 

 larger than fore wdngs, both folded like fans. The body is 

 hairy, rarely scaly. The larvae are somewhat caterpillar- 

 like, usually live in the water in special cases, and are 

 apneustic. 



Order 16. Coleopiera; Beetles. Fore wings modified into 

 wing covers, hind wings folded when not in use. Larvae 

 very diverse, generally with feet. The little bee parasites 

 Strepsiptera are probably allied. 



Suctorial Mouth Parts (Haustellate). 



Order 17. Diptera; Two-winged flies. Mosquito, midge, 

 gnat, gad fly, house fly. Sucking mouth parts, but some- 

 times with power of biting. Two anterior transparent, 

 unfolded wings and posterior "balancers" or "halteres." 

 Lar^•a usually a footless maggot, without a distinct head. 



Order 18. Siphonaptera or Aphaniptcra; Fleas. Wingless. 

 No compound eyes. Ectoparasitic. Larva a footless 

 maggot. 



Order 19. Lepidoptcra: Butterflies, moths. Two pairs 

 of uniform, scaly wings. Larva, caterpillar. 



Mouth Parts Developed j or Biting and Sucking. 



Order 20. Hymenoptera; Ants, bees, wasps, gall flies, 

 saw flies, etc. Usually with four transparent wings. Lar\se 

 are footless grubs, except in saw flies. 



