INTRODUCTION. vii 



entomologists, and that its health may depend on 

 adequate control of flies and other insects respon- 

 sible for the transmission of malaria, yellow fever, 

 typhoid, filariasis, trench fever, and other diseases. 

 Some understanding of insects, and their role in 

 our lives, therefore concerns both those on the land 

 and city people, and the subject could with advan- 

 tage be more seriously studied in our schools. 



W. B. GURNEY. 



