X PREFACE, 



convey those practical direclious^ which in some 

 branches of the pursuit the student requires; — 

 and lastly, because by this form, the objection 

 against speaking of the manners and economy of 

 insects before entering upon the definition of 

 them, and explaining the terms of the science— a 

 retrograde course, which they have chosen from 

 their desire to present the most alluring side of 

 the science first — is in great measure, if not wholly, 

 obviated. 



Such is the plan which the authors chalked out 

 for themselves — a plan which in the execution 

 they have found so much more extensive than they 

 calculated upon, that, could they have foreseen 

 the piles of volumes through which it has entailed 

 Tjpon them the labour of wading, often to glean 

 scarcely more than a single fact — the numerous 

 anatomical and technological investigations which 

 \t has called for — and the long correspondence, 

 almost as bulky as the entire work, unavoidably 

 rendered necessary by the distant residence of the 

 parties — they would have shrunk from an under- 

 taking, of which the profit, if by great chance 

 ihere should be any, could not be expected to 

 repay even the cost of books required in it, and 

 from which any fame must necessarily be confined 

 to a very limited circle. But having entered upon 

 it^ they have persevered; and if they succeed in 



