HYMENOPTERA. 369 



Neuroptera, or Nerve-winged Insects, as Dragon Flies 

 and their allies. 



Fig. 271. 



Dragon-Fly. 



SUB-SECTION I.* 



THE SUB-ORDER OF HYMENOPTERA, OR MEMBRANOUS-WINGED 



INSECTS. 



THE Sub-Order of Hymenoptera comprises insects with 

 four membranous and more or less transparent ' wings, 

 the hind pair the smaller, and all traversed by a few 

 irregularly branching veins. These insects have four 

 jaws, the upper pair horny and fitted for biting or cut- 

 ting, and the lower pair longer, softer, and with the lower 

 lip adapted for collecting honey. The males have no 

 weapons except their jaws ; but the females are provided 

 with either a piercer or a sting in the hind extremity of 

 the body. They all undergo a complete transformation 

 in coming to maturity ; but the Piercers differ from the 

 Stingers in their early stages. The young of the latter 



* Contrary to the general plan of this book, a Sub-Section is devoted to 

 each Sub-Order of Insects proper. This is done mainly for the sake of 

 convenience, and to give greater prominence to these groups, which, until 

 recently, have been treated as Orders. 



16* X 



