X PREFACE. 



convey those practical directions, 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 fore- 

 seen the piles of volumes through which it has 

 entailed upon them the labour of wading, often 

 to glean scarcely more than a single fact — the 

 numerous anatomical and technological investi- 

 gations which it has called for — and the long- cor- 

 respondence, almost as bulky as the entire work, 

 unavoidably rendered necessary by the distant 

 residence of the parties — they would have shrunk 

 from an undertaking-, of which the profit, if by 

 great chance there 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 



