[ i83 ] 
Though the Aphides are diftinguifhed by Linnaeus ' 
into more than thirty fpecies; ftlll 1 am fatisfied, 
from my own obfervation, the diftindl fpecies are 
even double that number: nor can I altogether 
agree with this ingenious author, that there are a 
greater variety of plants producing Aphides, than 
there are different forts of this infed:. Where plants 
are of a like nature, they are ufually frequented by 
the fame infeds ; but many of thefe plants will be 
found to fupport two or more quite different forts. 
On the peach and nedarine indeed the Aphides are 
the fame, nor do I find on thefe trees more than one 
fort. The plum tree, on the other hand, has two 
forts, very diffind from each other: one of a yei- 
lowifh. green, with a round fhort body j the other 
of a bluifh^green, as it were enameled with white, 
and the fhape more oblong. On the goofberry-bufh .> 
and ‘currant the fame Aphides may be found ; but 
each of thefe is inhabited by two very different 
fpecies: one being of a dufky green, with a fhort' 
plump body ; the other of a paler green, the body 
more taper, and tranfverfly wrinkled. To thefe in- 
ftances I muff further add, that the rofe-tree fup- 
ports not lefs than three diffind fpecies : The largeff 
of which is of a deep green, having long legs of a 
brownifh caff, with the joints of a very dark brown, 
as are alfo the horns and antennas > a fecond fort is 
paler green, has much fhorter legs, and a more flat 
body i the third fort is of a pale red, its body tranf- 
ver% wrinkled, and is moff frequently on the fweet- 
brier. It not being, however, fo much my inten- 
tion to enumerate the different fpecies of thefe in- 
feds, as to give fome infight into their extraordi- 
nary 
