[ i88 ] 
original flruflure, as on the quantity or quality of the 
nourifhment wherewith they are fupplied : it being 
frequently obfervable, that thofe on a fucculcnt flioot 
have few or none with wings among them ; while 
others of the fame generation, on a lefs tender 
branch, are moft of them winged : as if the firfl 
rudiments of the wings werecompofed in the former, 
while nature thought proper to expand them in the 
latter, that they might be more at liberty to fupply 
their wants. 
The increafe of thefe Infefls in the fummer time 
is fo very great, that, by wounding and exhaufling 
the tender fhoots, they would frequently fupprefs 
all vegetation, had they not many enemies which 
reftrain them. To enumerate the variety of other 
infe(n:s, that in their worm and fly flate are conftant- 
ly deftroying them, would exceed the bounds of 
my prefent defign : there is one, however, fo fingu- 
lar in the manner of executing its purpofe, that I 
cannot pafs it by without fome further notice. This 
is a very fmall black ichneumon fly, with a flender 
body, and very long antennae; which darts its 
pointed tail into the bodies of the Aphides, at the 
fame time depofiting an egg in each. This egg 
produces a worm, which feeds upon the contain- 
ing infe6f, till it has acquired its full growth ; wlien 
it is ufually changed to that kind of fly from whence 
it had its origin. In this, however, it is fometimes 
prevented by another foit of fmall black fly, wdfich 
wounds this worm through its pearl- like habitation ; 
and by laying one of its eggs therein, inlfead of the 
former fly, produces its own likenefs, 
A 
4 
T mufl 
