It is a recognized fact that the disuse of faculties inevitably leads
to deterioration.
There is a curious little plant called the sundew which grows in
marshes. A small fly alights on one of the leaves attracted by
the crimson hairs, and by the sticky liquid called the “dew.”
When the fly struggles to get free the hairs slowly curve round
him and trap him, at the same time pouring out more of the
dew. Presently the poor insect dies in that trap. Why does the
plant do this? Simply because it wants to eat the fly. The dew
is acid and dissolves the insect’s body, so that the plant can
absorb the nitrogen which it contains. The sundew once lived
in harmless plant fashion, for it belongs to the saxifrage
family, of which the other members are quite respectable and
hard-working plants, getting their living by honest root-work
in extracting their nitrogen out of the ground. When we examine
the sundew we find it has scarcely anything worthy the name
of a root. Long ago it seemed to dislike the wear and tear of
thrusting rootlets into the ground and seeking for food, so it
settled into a bog, where it could get water at least without
any trouble. There, as the roots had next to nothing to do, they
slowly dwindled away, as all things will dwindle which are not
used, whether they be plant-roots, or the limbs of animals, or
the minds of men.--“A Mountain Path.”
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