PREFACE 
HIS book has been written for those who wish 
to acquire some practical knowledge of farm 
and garden pests. It does not aim at dealing with 
all the numerous diseases which affect crops but 
rather at giving an accurate account of some of the 
commoner forms. It is hoped that a working know- 
ledge of these pests will be of great commercial value 
to farmers and market gardeners, and also that by 
their own observations they will be enabled to co- 
operate with those who are engaged in studying 
plant diseases in finding the most economical means 
of preventing the increasing annual losses due to these 
pests. 
Direct cures of some of the diseases are unknown; 
but even in these cases an accurate knowledge of the 
enemy will enable us to carry out remedial measures 
which will prevent big losses. 
Figs. 29, 316, 32, 34a, 36a, 37, 48, 49, and 50 
are taken from Curtis’s Farm Insects. Figs. 11, 14, 
23, and 24 from Diseases of Cultivated Plants and Trees 
