oy INSECTS IN GENERAL. 
345 
neither clear nor intelligible : It was then that men began 
to recognife, that fudden metamorphofes were none of 
the expedients which nature employs for the proda&ion 
of her offspring. This point was fuccefsfully laboured 
by Malphigi and Swammerdam, who carefully examined 
thofe infe&s that appear under different forms. By dif- 
fering them, a ftiort time before the period of their 
transformation, they obferved that their firft form was 
owing to a covering under which their different members 
were to acquire their proper fize and firmnefs : That all 
the parts of a butterfly, for example, were perfectly 
diftinct under the fkin of the worm which covered 
them ; and that under the cruftaceous fliell of the 
t'hryfalis, they were frill acquiring greater degrees 
of ftrength ; and were fad approaching to that ftate 
in which they were deftined to appear, when the ani- 
mal Ihould arrive at perfection, and be able to propa^ 
gate its kind. 
From the experiments of thefe naturalifts it appeared, 
that all the parts of the molt perfect winged infect were 
diftin&ly formed, and gradually acquired fize and ftrengh, 
under the different forms of a worm and a chryfalis, and 
that its progrefs and growth proceeded rather by deve- 
lopements, than by a real change : All the marvellous 
ideas conveyed by the terms transformation and meta- 
morphofes thus vanilbed ; and a beautiful analogy was 
eftablilhed between the growth of all organifed beings* 
whether in the animal or vegetable kingdoms, 
A filk worm, or the worm of a butterfly, which is a-* 
bout to enter into its chryfalis ftate, is obferved for foms 
time before to grow languid, and to ceafe from gnawing 
thofe plants of which it was formerly fo voracious : Af- 
ter having retired into a place fit for its purpofe, and ufi- 
Vol. III. X x dergoing 
