QF MANDIBULATA. 441 



ation of which is perfectly regular. The metamorphosis, 

 for instance, which is incomplete in Coleoptera, becomes 

 semicomplete in Orthoptera, subsemicomplete in the types 

 of the Neuroptera, obtect in Trichoptera, and then once 

 more again incomplete. As for the orders themselves, 

 we have seen them to pass most regularly into one another, 

 excepting, however, the chasms which occur between the 

 Coleoptera and Flymenoptera, and between the Tenthre- 

 dina and the Phryganida of Lamarck. 



These several remarks, which appear capable of very 

 great extension, together with a recollection of the pre- 

 ceding statements respecting the Haustellata, must, I think, 

 sufficiently evince the truth of Metamorphosis being the 

 chief principle upon which the natural orders of Aristotle's 

 Ptilota have been constructed. We observe that the 

 table of affinities, inaccurate and superficial as it may be, 

 turns out in the end to be also a table of the variation of 

 metamorphosis. Hence it may increase the conclusive- 

 ness of our principal affinities, if, in the first place, it can 

 be proved that metamorphosis is in these animals the 

 maximum state of a general law of Nature, by which the 

 whole organization of the being is gradually developed and 

 made fit for reproduction ; and if, secondly, we can show 

 that the most distinguished among naturalists have united 

 in expressing their conviction that considerations founded 

 on metamorphosis must ultimately produce the most na- 

 tural plan of entomological arrangement. Now, that nei- 

 ther of these propositions ought to be deemed incapable 

 of demonstration, may, I think, be inferred from the fol- 

 lowing slight sketch of some of the most remarkable truths 

 in Natural History. 



It was perfectly in unison with the innate propensity 



