Insects in the Garden 
301 
measures will have to be taken to keep these insects down. 
In infested districts the plants should be dusted with soot 
or lime, or sprinkled with paraffin and water, as for the 
Onion Fly, or the plant may be regularly sprinkled over 
with weak manure water, all of which make the leaves of 
the plants distasteful to the insects. If by chance some 
eggs have been laid, and blisters appear, the leaves should 
be opened at once and the maggot killed or the pieces of 
leaves with the blisters may be taken off and burned. 
Plant Lice or Aphides. — These are the best-known 
insects in the garden. Almost all plants are at times 
attacked by them. There are said to be about three 
hundred species, each having its own particular kind of 
plant to feed upon. They not only attack plants in the 
open, but also in the greenhouse. The Greenfly of our 
Roses, and the Blackfly of our Beans, are known only too 
well to all who have anything to do with a garden. 
Aphides have many curious characteristics. One of 
the most peculiar is the production of living young. These 
young will produce others, and so on. Thus we can 
account for the very rapid multiplication of these insects. 
Another characteristic is that there is very little difference 
between the appearance of the larva, the pupa, and the 
imago or perfect insect. These insects are furnished 
with a sucking mouth or proboscis. This is sharp, and 
pierces the plant, generally in the tender parts, i.e. the 
apex of the Bean plant, or of’ the Rose shoot, &c., from 
which they suck the sap. If they appear in large numbers, 
they may damage the plants so badly that they will die. 
These insects, like almost all others, breathe through pores 
which are situated in various parts of their body, known 
