442 HISTORY OF ENTOMOLOGY. 



It was a great point gained in the science to introduce 

 the consideration of the metamorphosis, and to employ 

 it in the extrication of the natural system : for though 

 when taken by itself it will, as in the table just given, 

 lead to an artificial arrangement, it furnishes a very use- 

 ful clue when the consideration of insects in their perfect 

 state is added to it. The tables contained in the Pro- 

 legomena to Ray's Historia Imectorum divide insects 

 into those which undergo no change of form, and those 

 which change their form. The arrangement of the 

 former (ApsTapogQaTot) was made by Willughby, who 

 subdivided them into Apoda and Pedata. As the only 

 insects included in the former section were the grubs of 

 CEstri, the remainder being Annelida, they need not be 

 included in our table. I have endeavoured to compress 

 these tables into as small a space as possible, by using 

 the Linnean terms for metamorphosis, and reducing 

 Ray's tribes of Orthoptera, Hemiptera, and Ncuroptera 

 to their modern denominations. 



Ray details at considerable length the various tribes 

 belonging to the four classes of metamorphosis establish- 

 ed by Swammerdam a . Most of his tribes indicate na- 

 tural groups of greater or less value : but some of his 

 larger groups are artificial, as you will see by the mere 

 inspection of the table. 



a Hist. Ins. Prolegom. ix.- 



