CHAPTER VI 

 NEUROPTEROID ORDERS 



OLDER writers on entomology placed several groups of 

 insects which we now class as separate orders together in 

 the old order Neuroptera. About the only character com- 

 mon to all the members of the group was the possession 

 of membranous wings with many veins. Even this char- 

 acter was by no means absolute. Later writers divided 

 the group into Neuroptera, proper, and Pseudo-Neurop- 

 tera,* the former including those groups which developed 

 indirectly and the latter those with direct development. 

 Both divisions normally have biting mouth-parts, although 

 in each group some are found with mouth-parts obsolete 

 or rudimentary. 



35. Pseudo-Neuroptera. Three orders of insects having 

 membranous wings, direct development, biting mouth- 

 parts and aquatic nymphs are included here. 



Plecoptera. Insects with four wings, the front pair 

 rather narrow, the hind pair broader and folded length- 

 wise, hidden, while at rest, beneath the front pair. The 

 mouth-parts usually well developed but sometimes nearly 

 obsolete and the nymphs living under stones in running 

 water which habit gives the adults the common name of 

 Stone-flies. Adults may be found in spring and early 

 summer about the streams in the evening and are fre- 



* Some groups at times placed with the Pseudo-Neuroptera we 

 prefer to consider elsewhere. These are the Termites and the Book- 

 lice and their relatives. 



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