Blanca) also forms part of the zoophyte, as a whole, in the same manner
as the roots of a tree form part of the whole tree, and not of the
individual leaf or flower-buds.
In another elegant little coralline (Crisia?), each cell was furnished
with a long-toothed bristle, which had the power of moving quickly.
Each of these bristles and each of the vulture-like heads generally
moved quite independently of the others, but sometimes all on both
sides of a branch, sometimes only those on one side, moved together
coinstantaneously, sometimes each moved in regular order one after
another. In these actions we apparently behold as perfect a
transmission of will in the zoophyte, though composed of thousands of
distinct polypi, as in any single animal. The case, indeed, is not
different from that of the sea-pens, which, when touched, drew
themselves into the sand on the coast of Bahia Blanca. I will state
one other instance of uniform action, though of a very different
nature, in a zoophyte closely allied to Clytia, and therefore very
simply organized. Having kept a large tuft of it in a basin of
salt-water, when it was dark I found that as often as I rubbed any part
of a branch, the whole became strongly phosphorescent with a green
light: I do not think I ever saw any object more beautifully so. But
the remarkable circumstance was, that the flashes of light always
proceeded up the branches, from the base towards the extremities.
The examination of these compound animals was always very interesting
to me. What can be more remarkable that to see a plant-like body
producing an egg, capable of swimming about and of choosing a proper
place to adhere to, which then sprouts into branches, each crowded with
innumerable distinct animals, often of complicated organizations. The
branches, moreover, as we have just seen, sometimes possess organs
capable of movement and independent of the polypi. Surprising as this
union of separate individuals in common stock must always appear, every
tree displays the same fact, for buds must be considered as individual
plants. It is, however, natural to consider a polypus, furnished with a
mouth, intestines, and other organs, as a distinct individual, whereas
the individuality of a leaf-bud is not easily realised, so that the
union of separate individuals in a common body is more striking in a
coralline than in a tree. Our conception of a compound animal, where
in some respects the individuality of each is not completed, may be
aided, by reflecting on the production of two distinct creatures by
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