WITH THE PUCERONS. 219 
3. Of the Relation of Ants with the Gali 
Insects. 
We know that the gall insects as well 
as the pucerons, station themselves on the 
leaves and branches of trees, to: suck their 
juices. The mouth and the sexual parts 
are applied against the tree; the orifice, 
destined to reject the excess of their 
nourishment, is placed on the back. The 
ants are attracted by the gall insects as 
well.as the pucerons: Iam not the first to 
have observed it. It has been long known 
that the kermes, and the cochineal: in- 
sects, which are generally allied to our 
gall insects, are always accompanied by 
ants, but we were unacquainted with the 
reason for this intimacy. It had never 
been remarked, that the gall insects de- 
livered over to them, like the pucerons, 
a considerable portion of the fluids they 
extract. 
M. de Reaumur himself believed, 
that the puncture made upon the tree by 
the gall insects, continued to pour forth 
a fluid after they had withdrawn their 
L 2 
