8 THE LIFE-STORY OF INSECTS [CH. 



feeding voraciously for the purpose of acquiring a 

 large store of nutritive material, after which it was 

 believed to revert to the state of a second but far 

 larger egg, the pupa, from which the winged insect 

 could take origin. Others again, following de R6au- 

 mur (1734), have speculated whether the development 

 of pupa within larva, and of winged insect within 

 pupa might not be explained as abnormal births. 

 But a comparison of the transformation of butter- 

 flies with simpler insect life-stories will convince the 

 enquirer that no such heroic theories as these are 

 necessary. It will be realised that even the most 

 profound transformation among insects can be ex- 

 plained as a special case of growth. 



CHAPTER II 



GROWTH AND CHANGE 



THE caterpillar differs markedly from the butterfly. 

 As we pursue our studies of insect growth and trans- 

 formation we shall find that in some cases the differ- 

 ence between young and adult is much greater as for 

 example between the maggot and the house-fly, in 

 others far less as between the young and full-grown 

 grasshopper or plant-bug. It is evidently wise to 

 begin a general survey of the subject with some of 



