And it is in this way,
doubtless, that the Sea Anemone entraps its prey, or anything else that
may come in contact with its tentacles. But so far are these movements
from indicating of themselves the action of any instinctive principle,
that they are no proof of animality; for a precisely analogous power is
possessed by the sensitive plant known as the Fly-Trap of Venus
(_Dionoea muscipula_): "any insect touching the sensitive hairs on the
surface of its leaf instantly causes the leaf to shut up and enclose
the insect, as in a trap; nor is this all; a mucilaginous secretion
acts like a gastric juice on the captive, digests it, and renders it
assimilable by the plant, which thus feeds on the victim, as the
Actinea feeds on the Annelid or Crustacean it may entrap." In the
animal organization a large class of reflex actions are excited, not by
a direct influence, but indirectly by the agency of the nerves and
spinal cord. Such actions are essentially independent of the brain; for
they occur in animals which have no brain, and in those whose brain has
been removed. However marvellous these functions of organic life may
be, there is nothing in them at all resembling that agency properly
called instinct, which may be said to take the place in the inferior
tribes of reason in man.
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