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 Insectorum divide insects 
into those which undergo no change of form, and those 
which change their form. The arrangement of the 
former (Aft,sTUfiog<pu)Tu) was made by Willughby, who 
subdivided them into Apoda and Pedata. As the only 
insects included in the former section were the grubs of 
Qlstri, 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 Neuroptera 
to their modern denominations. 
Ray details at considerable length the various tribes 
belonging to the four classes of metamorphosis establish- 
ed by Swammerdam 3 . 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. 
n Hist. Ins. Prolegom. ix. — 
