vice in search of food for the tree, rejecting what is
unpalatable and forwarding what is useful for building up and
sustaining the monarch. Other cells take in necessary food from the
air. Others build up the trunk and its protective bark. Others, and
most important of all, go to make up the flowers of the tree and the
organs of reproduction which enable the tree to propagate its kind.

All this activity of the separate cells and combinations of cells is
taking place. And in addition there is that activity of them all in their
togetherness, that activity which keeps the cells together, and which
if relaxed for a moment would mean that the cells would all collapse
as the grains of dust in an eddying dust-devil at a street corner
collapse once the gust of wind which stirred them and keeps them
together drops away. What must be the intensity of life required to
develop the tree from the seed and to rear that giant straight up from
the level soil 200 feet into the air and maintain it there two hundred
years, we can only imagine; for to outward appearance the tree is
quite impassive. It does not move a muscle of its face to reveal the
intensity of life within.

The tree is characteristic of every living thing. Every plant and every
animal, however seemingly sluggish, is working to fulfil its life, to
nourish itself, to reproduce its kind.

* * *

Now, the amount of air and sunshine for plants may be practically
unlimited, but air and sunshine are not all that plants require. They
want soil and moisture as well. And the standing-room for plants is
strictly limited. The forest stretches away up to the snows; but there
it stops. Necessarily, therefore, there must be the keenest and most
incessant struggle among the plants for standing-room. Only a
comparatively few can be accommodated. The rest cannot survive.
And as the number of plants which can survive is thus limited, the
number of animals is limited also, for animals are dependent on
plants. Plants, therefore, in spite of their eminently pacific
appearance are engaged in a fierce struggle with one another for
standing-room. And animals are likewise engaged in a struggle
among themselves for the plants.

There is competition among the roots of the different individual
plants for the food and water of the soil. And there is competition
among the leaves for the sunlight. Each plant is pushing its roots
downwards and spreading outward for more food and to root itself
m