multifarious mouths. I think that is as good an example of a
zoological co-operative store as you can well have. Such are these
wonderful creatures. But they are capable not only of multiplying in
this way, but in other ways, by having a more ordinary and regular kind
of offspring. Little eggs are hatched and the young are passed out by
the way of the mouth, and they go swimming about as little oval bodies
covered with a very curious kind of hairlike processes. Each of these
processes is capable of striking water like an oar; and the consequence
is that the young creature is propelled through the water. So that you
have the young polype floating about in this fashion, covered by its
'vibratile cilia', as these long filaments, which are capable of
vibration are termed. And thus, although the polype itself may be a
fixed creature unable to move about, it is able to spread its offspring
over great areas. For these creatures not only propel themselves, but
while swimming about in the sea for many hours, or perhaps days, it
will be obvious that they must be carried hither and thither by the
currents of the sea, which not unfrequently move at the rate of one or
two miles an hour. Thus, in the course of a few days, the offspring of
this stationary creature may be carried to a very great distance from
its parent; and having been so carried it loses these organs by which
it is propelled, and settles down upon the bottom of the sea and grows
up again into the form and condition of its parents. So that if you
suppose a single polype of this kind settled upon the bottom of the
sea, it may by these various methods--that is to say, by cutting itself
in two, which we call "fission," or by budding; or by sending out these
swimming embryos,--multiply itself to an enormous extent, and give rise
to thousands, or millions, of progeny in a comparatively short time;
and these thousands, or millions, of progeny may cover a very large
surface of the sea bottom; in fact, you will readily perceive that, give
them time, and there is no limit to the surface which they may cover.