THE PLANT-LICE. 
235 
Concord, N. H., to whom I am indebted for much valuable 
information respecting the wheat-fly, or Cecidomyia Tritici , 
has discovered another pernicious insect in the ears of srrow- 
ing wheat. It seems to agree with the accounts of the Thrips 
cerealium, which sometimes infests wheat, in Europe, to a 
great extent. -This insect, in its larva state, is smaller than 
the wheat maggot, is orange-colored, and is provided with 
six legs, two antennae, and a short beak, and is very nimble 
in its motions. It is supposed to suck out the juices of the 
seed, thus causing the latter to shrink, and become what the 
English farmers call pungled. This little pest may proba- 
bly be destroyed by giving the grain a thorough coating of 
slacked lime. 
Aphides, or plant-lice, as they are usually called, are 
among the most extraordinary of insects. They are found 
upon almost all parts of plants, the roots, stems, young- 
shoots, buds, and leaves, and there is scarcely a plant which 
does not harbor one or two kinds peculiar to itself. They 
are, moreover, exceedingly prolific, for Reaumur has proved 
that one individual, in five generations, may become the 
progenitor of nearly six thousand millions of descendants. 
It often happens, that the succulent extremities and stems 
of plants will, in an incredibly short space of time, become 
completely coated with a living mass of these little lice. 
These are usually wingless, consisting of the young and of 
the females only; for winged individuals appear only at 
particular seasons, usually in the autumn, hut sometimes in 
the spring, and these are small males and larger females. 
After pairing, the latter lay their eggs upon or near the 
leaf-buds of the plant upon which they live, and, together 
with the males, soon afterwards perish. 
The genus to which plant-lice belong is called Aphis, 
(1 late III. b ig. 4, Aphis mali,') from a Greek word which 
signifies to exhaust. I he following are the principal char- 
acters by which they may be distinguished from other insects. 
Their bodies are short, oval, and soft, and ax - e furnished at 
