CHapter III. 
THE ROOT. 
The root, we have seen, is the organ that relates 
the plant to the soil, by means of which it is held 
firmly in position, and through which it receives its 
supplies of water and minerals. It now remains to 
examine in detail the different structures that comprise 
the root, to study their origin, growth, and develop- 
ment, and, above all, to discover the function of each. 
We shall thus see how the root helps to fit the plant 
to its environment, always remembering that it is 
with the soil, which forms but part of that environment, 
that this organ is principally concerned. 
We have already noted the lavish root production 
in certain well known plants, and the enormous length 
that the roots may collectively attain. We shall now 
see how, and in what order they are produced. Obtain 
two boxes each with one sloping glass side. Fill these 
with loose moist soil, and against the glass, just below 
the surface of the soil, place in the first, two or three 
well soaked broad bean seeds (Fig. 32), and in the 
second, the same number of maize grains. Cover both 
boxes with a black cloth, so that no light may reach the 
germinating seeds. Observations made from time to 
time show that first the tiny radicle appears, and, no 
matter in what direction it may escape from the 
micropyle, it will eventually make its way straight 
downwards along the surface of the glass. Up to this 
stage, except in point of size, there is no notable 
difference between the rootlets of bean and maize, but 
Soon we come to the parting of the ways. In the bean, 
the radicle becomes thicker, lenethens indefinitely and 
gives off side branches in reeular succession, so that 
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