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Garden Work 
and by suction extract the substance from it. The damage 
is not apparent at first, but as time goes on, and the insects 
increase, the plant ceases to make any growth, gradually 
becoming stunted, and finally dies. 
We also have the insects with the “biting mouths”. 
These have strong jaws, and either eat their way over 
the surface of the plant or right through it. The depre- 
dations of these insects are immediately seen, either where 
they have eaten their way over or through the plant. 
Before we proceed further, let us turn our attention for 
a short time to a typical insect, examine it, and go through 
its life-history. First we start with the egg. Segmenta- 
tion takes place and goes on rapidly, and from the egg 
there is developed a living creature. This is, however, 
not a mature insect, it is only a larva, and will, in this 
stage, do the greatest amount of harm. The larvae are 
extremely difficult to satisfy with food, for they are feed- 
ing all the time during this stage of their development. 
They increase in size very quickly, and when the skin gets 
too tight to hold them they cast it off, another one in the 
meantime having been growing underneath. When this 
becomes too tight it is also thrown off, and so on, until the 
larva attains its full size. When this stage is reached the 
skin splits open again, but this time, instead of a larva of 
a different size, quite a distinct creature appears. This is a 
chrysalis or pupa. The pupa stage is generally passed in 
a period of rest. Before the larva casts its last skin a case 
is formed under that skin, and it is in this case that the 
pupal stage is passed. This covering is called the cocoon, 
and may often be found in the soil among leaves, &c. It 
is in this pupal stage that the changes are going on which 
