ELEMENTARY ENTOMOLOGY 



CHAPTER I 



INTRODUCTION 



A professor of entomology in one of the leading universities 

 has recently been quoted as saying that this is " the age of in- 

 sects." Doubtless most of us have been accustomed to consider it 

 "the age of man," but although man's sway is dominant in all 

 parts of the earth, there is considerable evidence that, from a purely 

 biological standpoint, insects are the most characteristic form of 

 life of the present age, and the statement quoted challenges our 

 attention for more than a passing consideration. 



That such a statement should be made by a well-known ento- 

 mologist, and should be widely quoted, is significant of the present 

 attitude of the public toward insect life, which has changed radi- 

 cally during the last generation. Not many years ago the entomol- 

 ogist, or " bug collector," was looked upon as a harmless individual 

 who amused himself with his hobby ; and as he was met with his 

 butterfly net, the passer-by might lift his eyebrows as if questioning 

 whether a grown man who would devote himself to such insignifi- 

 cant creatures was really quite normal. 



To-day the public has come to appreciate that insect life plays a 

 most important part in the economy of our civilization. Some of 

 the problems which require the work of the trained entomologist are 

 worthy of the highest scientific training and best executive ability. 



Insects and disease. The modern methods of sanitation for the 

 control of malarial fever and yellow fever involve the control of 

 mosquitoes, which transmit these diseases. More and more the 

 sanitary measures which are making the tropics habitable for the 

 more northern races of man are being made possible by a knowl- 

 edge of the relation of insect life to the transmission of disease. 

 Even the common house-fly, formerly considered a mere nuisance, 



