PREFACE. 



The majority of Entomological Works which have appeared, 

 during the last quarter of a century, and which have not only 

 given so great an impulse to the science, but have also imparted 

 to it a philosophical character, of which it was previously des- 

 titute, may be desci'ibed as exhibiting either generalised views 

 of the subject; or, of elaborate technical details of the genera 

 and species of insects. 



Thus, whilst the delightful Introduction to Entomology of 

 Messrs. Kirby and Spence, followed by Burmeister's Manual, 

 and, at more humble distances, by the Insect Architecture, Trans- 

 formations and Miscellanies, the Grammar of Entomology, by 

 Newman, and my Entomologisf s Text-Book, have made us ac- 

 quainted with the general details of insect habits and structure ; 

 the Illustrations and Descriptions of the Genera of British Insects 

 of Curtis, the Illustrations of British Entomology of Stephens, 

 the Essay on the Eossorial Hymenoptera of Shuckard, the Lepi- 

 doptera Britannica of HaAvorth, &c., have led us to the investi- 

 gation of the minute details of generic and specific distinctions. 

 The nature of these works necessarily rendered them essentially 

 different in the information they conveyed; indeed, owino- to 

 the greater number of organs possessed by insects over the 

 higher animals, and the consequently great modifications to 

 which they are subjected in the different groups, in order to fit 

 them for performing their various functions, it must be evident 

 that the former class of works, unless extended to a oreat 

 number of volumes, must necessarily exclude the description 



