^iii PREFACE. 



with reference to the anatomy and physiology of 

 insects, they could no where meet with a full 

 and accurate generalization of the various facts 

 connected with these subjects, scattered here and 

 there in the pages of the authors who have stu- 

 died them. 



They therefore resolved to begin, in some mea- 

 sure, de novo — to institute a rigorous revision of 

 the terms employed, making such additions and 

 improvements as might seem to be called for ; 

 and to attempt a more complete and connected 

 account of the existing discoveries respecting the 

 anatomical and physiological departments of the 

 science than has yet been given to the world : — 

 and to these two points their plan at the outset 

 was limited. 



It soon, however, occurred to them, that it 

 would be of little use to write a book which no 

 one would peruse ; and that in the present age of 

 love for light reading, there could not be much 

 hope of leading students to the dry abstractions 

 of the science, unless they were conducted through 

 the attractive portal of the economy and natural 

 history of its objects. To this department, there- 

 fore, they resolved to devote the first and most con- 

 siderable portion of their intended work, bringing 

 into one point of view, under distinct heads, the 

 most interesting discoveries of Reaumur, De Gear, 



