12 INTRODUCTION. 



artificial; and almost every author previous to Latreille, 

 while he altered the principle, followed Linnaeus in the de- 

 tails of arrangement. Hence arose the abuse of the Essential 

 Character; a term excellent and useful in the abstract idea 

 given of it by Linnaeus and Fabricius, but which, being 

 founded on one or two favourite parts only of the insect, 

 soon became little else than a magical name for each prin- 

 ciple of classification, whatever this might have been, and 

 from which the entomologist fancied Nature could make 

 no appeal. One author accordingly made use of the 

 antenna? alone for his system ; another of the tarsi ; and a 

 third of the instrumenta cibaria: and each, according to his 

 own plan, took his essential character solely from the modi- 

 fications of the favourite organ which he had chosen to be 

 the keystone of his system. It will therefore cease to excite 

 surprise that Entomology, generally speaking, should be still 

 in its infancy. The French entomologists have, it is true, 

 made use of a system founded upon and combined of all 

 the parts of an insect. Yet, by supposing Nature to have 

 been absolutely governed by a set of rules which they 

 themselves laid down, and by scarcely allowing the possi- 

 bility of her making exceptions to these rules, they have 

 done little more by their innovations, than given to the 

 world an additional artificial system. 



