120 THE INSECT WORLD. 
wingless (Figs. 89,90). The last-named are the largest: and are 
a line and a half long. They are entirely green, except two parts, 

Figs. 89, 90.—Wingless Aphides, or Plant-lice (magnified). 
of which we will speak immediately. The body is oval; the head 
is small, and furnished with two brown eyes. The skin smooth, 
and tight drawn over the body. The antenne, which are very 
long and slender, almost exceed the body in length. The six legs 
are long and slim, and the feet terminated in two hooks, short. 
On the upper part of the body are two small cylindrical horns, 
surmounted by a small knob. ‘The antennee and these horns are 
black. 
The winged individuals are of the same size as these, but of a 
dark green, mixed with black. The wings are transparent, the 
upper ones as long again as the body. The young shoots of the 
elder-tree are often covered with black plant-lice, or with 
those of a ‘greenish-black colour, all round their circumference 
for the length of from a foot to a foot and a half. ‘They are 
crowded one against the other, and sometimes there are two layers 
of them. 
If observed without moving the plant about, they appear to be 
tranquil and inactive. They are, however, then absorbing from 
the plant the nourishment it should have; piercing with the 
point of their trunks the epidermis of the leaves or stalks, and 
drawing from them a nourishing liquid. 
But this occupation is confined to those which are on the plant 
itself. Those which, on account of the enormous agglomeration 
of these insects, walk, not on the branch, but on other plant-lice, 
and cannot therefore suck the sap of the plant, are employed 
entirely in preserving and multiplying their species. 
Réaumur often saw the latter, easily recognised by their great 
size, giving birth to little plant-lice, which are quite alive when 
