CHAPTER VII 



GROWING INSECTS AND THEIR SURROUNDINGS 



IN the earlier chapters of this volume some account has been 

 given of the growth and accompanying transformations 

 of a number of insects of various orders, so as to illustrate 

 varying degrees of outward and inward change during develop- 

 ment, and to display the greatly differing modifications of 

 form assumed by different insect larvae. In these descriptions, 

 some attention was necessarily paid to the manner of life of 

 these young insects, and it was seen how their structure is 

 adapted to the surroundings in which they have to live and 

 feed. It may now be advantageous to give further examples 

 of the variety of form displayed by insects during their period 

 of growth, with especial reference to this important question 

 of environment. The development of any animal from the 

 fertilized egg to the close of life may be considered as deter- 

 mined by the factors and tendencies inherited through an 

 immensely extended line of ancestry, and by the influences 

 brought to bear on the individual through the surroundings 

 in which it has to live. A discussion as to the detailed opera- 

 tion and the relative importance of heredity and environment 

 in the moulding of the organism would be beyond the scope 

 of this book, but a study of insect transformation from the 

 environmental point of view provides many facts, highly 

 interesting and suggestive with regard to these problems, 

 which have been, and still are, the subject of eager discussion 

 among students of living nature. 1 To the biologist the term 

 " environment " or " surroundings " suggests a survey of the 

 conditions of a creature's life in the widest sense where it 

 lives, how it feeds, its experiences and activities, what draw- 

 backs in its life-relations it may have to overcome, what other 

 living creatures are its competitors, or maybe its deadly 



1 J. Arthur Thomson: "Heredity". London, 1919. 



1 88 



