PREFACE 



poison sprays and other artificial appliances, supple- 

 mented by useful carnivorous and parasitic insects. 



The birds alone can turn the scale in our favour. 



The principal object of this book is to endeavour to 

 show the extent of the depredations of insects, and 

 the usefulness, nay, the necessity of birds in our fight 

 for supremacy against the greatest enemy of the human 

 race — the insects and allied forms of life. 



In the compilation of these books I was helped by 

 valuable field observations on the nesting habits and 

 diet of birds by my son Vivian ; also by my son 

 Desmond with many pen and ink sketches. 



THE AUTHOR. 



Port Elizabeth, 1923. 



IX 



