PREFACE. 



organization been added to the above claims in 

 favour of precedence, I should certainly have been 

 disposed to allow more weight to the arguments 

 adduced. Burmeister, Dufour, and others, have 

 certainly paid some attention to the internal anatomy 

 of insects ; but their selection has been of a parti- 

 cular organ for classification, and not the general 

 anatomy. The organ selected was the alimentary 

 canal ; and accordingly as its length varied, being 

 short m the carnivorous species, and long in the 

 herbivorous, so they have partly allowed these facts 

 to operate on classification. The length of the 

 alimentary canal, however, cannot be decisive of 

 the habits of an animal, or a vegetable feeder 

 in the class Insecta ; nor do I think that the 

 alimentary canal is a proper criterion on which to 

 found a scientific arrangement, either in the verte- 

 brated or invertebrated animals j since, although 

 the characters derived from it may hold good in 

 many instances, the exceptions with regard to 

 Insecta are far too numerous to justify any reliance 

 upon it. If the alimentary canal be taken as a 

 leading character, it will place those with the 

 shortest canal, the true carnivorous animals, above 

 the omnivorous ; indeed man himself, if the rule is 

 strictly followed out, will be placed below the feline 



