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INSECT LIFE. 



Order Plecoptera (Ple-cop'te-ra). 

 The Stone-flies. 



The members of this order have four membranous 

 wings, with comparatively few or with many cross-veins ; 

 the hind wings are much larger than the fore wings, and 

 are folded in plaits and lie upon the abdomen when at 

 rest. The mouth-parts are of the biting type of structure, 

 but are frequently poorly developed. The metamorphosis 

 is incomplete. 



The name of this order is from two Greek words: 

 plecos, plaited, and pteron, a wing. It refers to the 

 way in which the hind wings are 



Fig. 38. — A stone-fly. 



Fig. 39. — A nymph of a 

 stone-fly. 



folded when at rest. Fig. 38 represents one of the 

 larger members of this order with the wings of one 

 side spread, and Fig. 39 represents a nymph. Work 

 on these insects is outlined in the chapter on Brook 

 Life. 



