ORDER NEUROPTERA. 



CHAPTER VIII. 

 THE FLAT-WINGED NEUROPTERA AND THE CADDIS-FLIES. 



NEUROPTERA Characters Habits Classification PLANIPENNIA MEGALOPTERA Characters THE MYRMELEON- 

 TIDJE, OR ANT-LIONS Habits Capture of their Prey THE HEMEROBID.E The Golden-eyed Fly The Genus Nemoptera 

 THE MAXTISPIDJE THE SIALID^E The Sialis lutariaThe Snake-flies, or Camel-flies THE PANORPIDA: The Scor- 

 pion-fly Habits Genus Bittacus Genus Boreus TEICHOPTERA Caddis-flies Difliculty of Assigning their Proper 

 position McLachlan's Classification Characters Distribution Metamorphoses The Phryganeidse The Lamnophi- 

 lidaj The Sericostomidse The Leptoceridae The Hydropsychidse The Rhyacophilidse The Hydroptilida;. 



THE order Neuroptera of the older entomologists included all the insects which possess four 

 membranous wings more or less elaborately veined, but not after the Hymenopterous type, the veins 

 running straight through the wing, with a larger or smaller number of branches, and either 

 simply parallel or united by more or less numerous cross veins. The peculiar arrangement o 

 cells seen in the fore wings of the Hymenoptera (see figure on p. 354, Vol. V.) never occurs 

 in these insects. Between the insects thus brought together by the possession of wings more or less 

 similar in character there is, however, a very important difference. Some of them, and the larger 



number, only pass 

 through an imper- 

 fect metamorphosis, 

 being active and 

 voracious in all 

 stages of their exist- 

 ence ; while the rest 

 have a complete 

 metamorphosis, the 

 larva being quite 

 different in struc- 

 ture from the per- 

 fect insect, and the 

 pupa quiescent. 



The latter con- 

 stitute the order 

 Neuroptera of mo- 

 dern authors, and 

 they may be defined 

 as insects with a 

 perfect metamor- 

 COMMOX AXT-LION. phosis, a mandibu- 



late mouth, a free 



prothorax, and four more or less veined membranous wings. It must be confessed, however, that in, 

 this definition the character of the metamorphosis is the only one separating them from the other 

 membranous-winged insects which were formerly associated with them, but are now commonly 

 referred to the great order Orthoptera ; and further, that from circumstances, especially the 

 remarkable differences presented by the members of both groups among themselves, it is exceedingly 

 difficult to frame a broad definition, applicable to the perfect insects alone, which will serve for the 

 discrimination of the two series. 



There is one character, however, which almost universally holds good, and this is derived from 

 the structure of the ligula. Throughout the more highly organised Orthoptera the ligula is, almost 

 without exception, divided or cleft in front, either into two or four lobes, and the indications of: 

 division may even continue clown into the basal part of the labium, showing very clearly the original 

 construction of the whole labium out of a pair of organs similar to the maxillae. In the true 

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