OF MANDIBULATA. 421 



animals being in a manner insulated is very advantageous 

 for those who may be in search of a natural method of 

 distribution, because the most general ideas which can be 

 formed of it are thus confined within certain limits, and 

 the greatest evil of generalizing is thus in limine counter- 

 acted. 



It was from such reflections that I had much less 

 reluctance to confide in the accuracy of my eye in seizing 

 the natural affinities of the Coleoptera than I should other- 

 wise perhaps have experienced, being convinced that the 

 peculiarities of the order made it equally impossible to in- 

 sert any thing in it which ought not to be there, as to 

 withdraw from its just province any insect which might 

 be truly Coleopterous. Thus, I threw the whole into the 

 great groups which occurred most obviously to the sight, 

 leaving out of consideration all genera with respect to whose 

 affinities there was the least reason for doubt. It then 

 became necessary, in pursuance of that elementary maxim 

 of Natural History, " Character non est id genus fiat y sed 

 ut genus noscatur," to seek for general characters where- 

 with the divisions thus obtained might be defined ; and 

 for some time I could discover none that were in any 

 manner applicable. Some satisfaction, therefore, was ex- 

 perienced when, on happening at length to think of their 

 larva?, I discovered that each of my groups had, as far as 

 my knowledge of them went, a peculiarity of character, 

 This, however, like all other natural peculiarities which 

 distinguish groups, can only be described by an enumera- 

 tion of the types to which the animals composing each 

 group more or less approach ; or in this case rather by a 

 classification of the types to which the larva? of each 

 group may, in a greater or less degree, be assimilated. Of 



