thing that comes into my head. Let us suppose it to be a forest,--
the manner in which it sows itself in the plain, and spreads abroad.
1. Beginning with a small aggregate, it increases imperceptibly in
mass, and so forth. Exactly the same thing takes place in the
fields, when they gradually seed themselves down, and bring forth a
forest. 2. In the beginning the structure is simple: afterwards it
increases in complication, and so forth. Exactly the same thing
happens with the forest,--in the first place, there were only bitch-
trees, then came brush-wood and hazel-bushes; at first all grow
erect, then they interlace their branches. 3. The interdependence
of the parts is so augmented, that the life of each part depends on
the life and activity of the remaining parts. It is precisely so
with the forest,--the hazel-bush warms the tree-boles (cut it down,
and the other trees will freeze), the hazel-bush protects from the
wind, the seed-bearing trees carry on reproduction, the tall and
leafy trees afford shade, and the life of one tree depends on the
life of another. 4. The separate parts may die, but the whole
lives. Exactly the case with the forest. The forest does not mourn
one tree.

Having proved that, in accordance with this theory, you may regard
the forest as an organism, you fancy that you have proved to the
disciples of the organic doctrine the error of their definition.
Nothing of the sort. The definition which they give to the organism
is so inaccurate and so elastic that under this definition they may
include what they will. "Yes," they say; "and the forest may also
be regarded as an organism. The forest is mutual re-action of
individuals, which do not annihilate each other,--an aggregate; its
parts may also enter into a more intimate union, as the hive of bees
constitutes itself an organism." Then you will say, "If that is so,