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 Reau- 

 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 



