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OUR HOUSEHOLD INSECTS 



wings), an order which we have not hitherto met with 

 amongst our domestic pests. It is a very mixed assem- 

 blage, containing, for want of a better arrangement, in 

 addition to the Psocidce, such insects as the lace-wing 

 flies, scorpion-flies, May-flies, white ants, and, according 

 to some authors, dragon-flies as well. The most uniform 

 and characteristic feature of the majority of these in- 

 sects is that the nervures of the wing are extremely 



FIG. 105. A. Fore-wing of Lace-wing- Fly (Chrysopa vulgaris). 

 B. Fore-wing of Psocus longicornis. 



numerous, dividing its surface into so large a number of 

 minute areas that it appears to be covered with a small- 

 meshed network, whence the name Neuroptera. The 

 Psocidce, however, are but an outlying section of this 

 oroup, and do not exhibit such a minute subdivision of 

 the wing surface, as will be seen by comparing the 

 accompanying illustrations of the fore-wings of a lace- 

 wing fly and a Psocid (Fig. 105). For this reason, 

 these insects have sometimes been spoken of as Pseudo- 



