PREFACE. XI 



In the entomological arrangement I have mainly 

 followed that laid down by Prof. J. 0. Westwood in 

 his 'Introduction to the Modern Classification of 

 Insects,' and in mentioning this I cannot refrain from 

 also acknowledging the deep obligation I am under to 

 my much respected friend and honoured master in 

 the study of Entomology, not only for the information 

 derived from his published works, but for the scientific 

 aid which, in correspondence and in occasional 

 meetings, has extended over a large portion of a 

 life-time. 



In the special sections, I have endeavoured to follow 

 the lines laid down by our leading specialists, as in 

 'British Beetles,' by the late E. C. Rye; 'British 

 Aphides,' by G. B. Buckton, F.R.S. ; and others of 

 similar known standing. In the practical part, I have 

 endeavoured to work out the teaching which appears 

 to me to be conveyed by the observations which now, 

 for many years, have been placed in my hands by 

 agriculturists throughout our country ; and should 

 this little book prove of agricultural service, I much 

 desire to point out that this will be not from specula- 

 tive or theoretical views, but in great part from the 



