10 
tlie least verdure, and on some kind of apple trees 
before the bud has at all burst its exterior cuticle. 
It is very remaikable, but quite certain, that the first 
g'eneration of this species is produced from an egg", 
while all the succeeding’ generations, which are 
many, both in their larvae and perfect state, ai’e 
viviparous. The eggs are deposited in the month 
of October on tlie spurs and branches of the tree, 
where, and in which state, they withstand the 
winter months, without sustaining’ the least injury. 
As the reviving spring approaches to bring vege- 
tation into existence, it appears to be provided 
that the same cause should move the ova, to pro- 
duce those little animals, at the same time. They 
immediately commence feeding upon the bursting 
buds; but it does not appear that so much injury 
is done to the buds as we might suppose from 
the multiplicity of eggs there sometimes ai’e till 
the succeeding brood, perhaps owing to the cold 
which mostly prevails early in the spring months, 
and by which they are caused to be chiefly torjiid. 
The next brood, however, which is viviparously 
produced from them in tlu’ee or fom’ weeks after 
quitting tlie embryo, when the weather becomes 
more exhilerating, soon furnishes the underside of 
the leaves with a multitudinous progeny, and goes 
on increasing so rapidly that in a few days the insects 
have to enlarge their possessions, which they do 
even so as to envelop the whole end of the young 
shoots, and so as to have to rest one ujion another. 
So productive is this tribe of insects that Kikby in- 
