CLASS' INSECTS. 



443 



wings, instead of being reticulated like lace, are divided into 

 a certain number of tolerably large cellules by horny nervures, 

 and they cross each other horizontally on the body during 

 repose. These integuments are not very hard, and the 

 abdomen of the female is terminated by a wimble or dart. 



These insects undergo a complete metamorphosis. The 

 larva, sometimes deprived of wings, resembles a worm ; at 

 other times, having six feet, with hooks, and often also from 

 twelve to sixteen membranous feet, it more resembles a cater- 

 pillar. In both cases it has a scaly head, with mandibles, 

 jaws, and a lip, at the extremity of which is a winder for the 

 passage of the silky matter of which the cocoon is to be con- 

 structed. The regime of these larvae varies much. Several 



Fig. 469. Dragon Fly (Libellula depressa). 



require foreign aid, and are brought up in common by sterile 

 individuals, reunited into a society, as we have seen in speak- 

 ing of bees ( 332). The nymph remains without nourish- 

 ment, and in complete repose. Finally, in their perfect state, 

 the hymenoptera live almost all on flowers, and they die at 

 the end of the first year of their existence. 



This order comprises most of the insects more remarkable 

 for their instincts, such as ants, bees (Fig. 131), and wasps ; to 

 it also belong the humble bee (Fig. 131), the xylocopes (Fig. 



