CHIEF ENTOMOLOGICAL CLASSIFICATIONS AND SYGTKMP. 023 



b. b. Four wings, generally covered with scales ; six biliary 

 vessels ; larvae with feet and a distinct head ; the maxillae 

 forming a spiral tongue ; prothorax not free, but small, 

 and closely connected with the mesothorax. 

 6. Order Lepidoptera. 



/3. Mouths with distinct, biting mandibles. 



a. a. Four naked wings traversed by ramose nervures ; 

 larvae generally without head and feet, but sometimes with 

 both ; many biliary vessels ; prothorax not free. 



7- Order Hymenoptera. 



b. b. Anterior wings, horny elytra ; larvae with head, with or 

 without feet ; four or six biliary vessels ; prothorax always 

 free. 



8. Order Coleoptera. 



Our system is not acquainted with an order Aptera, which we have 

 found in the majority of the others, as in every case it is artificial, and 

 must embrace insects of the most dissimilar orders. The most distinct 

 proof in support of this assertion is furnished by the circumstance that 

 we find in the same family winged and apterous genera, contiguous 

 together, and, indeed, in many genera which we have before enu- 

 merated, the males winged, and the females apterous. From the prin- 

 ciples of the system we might expect a group containing insects with- 

 out any metamorphoses, but there cannot be such an one, as the idea 

 of an insect would be thereby annulled. All true insects whose meta- 

 morphosis has been denied by other entomologists belong to the group 

 with an imperfect metamorphosis, and were only considered as deficient 

 in it, because in them the organ is wanting in which we detect the 

 imperfect metamorphosis. If, for instance, an insect remains apterous 

 throughout its whole life, it loses the organ by which we distinguish 

 the imperfect metamorphosis, but in other respects its development is 

 conformable to those with an imperfect metamorphosis. We have 

 therefore applied the name given by Leach to those apterous insects, to 

 all with an imperfect metamorphosis, for in fact there is no difference 

 in the processes of development in each. This is the guide to the 

 correct estimation of our system. 



A difference of opinion may exist upon the application of the Lin- 

 naean names to our orders, as many orders contain entire families to 

 which those names do not apply, for instance, apterous insects. But I 

 think it better to retain an old characteristic name, than by means of 



