ted, looking like miniature dabs of jelly;
others attached head and tail to the side of the glass; others
floating on the surface of the water, their tail-ends sticking out and
serving to keep them from sinking; some of a beautiful grass-green
colour, others light brown or flesh colour, others almost white,
others red. These creatures may be cut into several parts, yet each
part will grow again into a perfect animal; young ones bud out of the
sides of the parents. Some have said that they can be turned inside
out, and find no inconvenience whatever from the operation. "But how,"
asked Willy, "could anybody manage to turn so small a thing as a hydra
inside out?" It does seem an impossible task, I confess, and a man
must have much skill and patience to enable him to accomplish it.
However, I will give you the description of an attempt made many years
ago by a celebrated naturalist of Geneva, named Trembley, who made the
hydrae or fresh-water polypes a study for many years. This is what
Trembley says:--"I begin by giving a worm to the polype on which I
wish to make an experiment, and when it is swallowed I begin
operations. It is well not to wait till the worm is much digested. I
put the polype, whose stomach is well filled, in a little water in the
hollow of my left hand; I then press it with a small forceps nearer to
the tail end than to the head. In this way I push the swallowed worm
against the mouth of the polype, which is thus forced to open, and by
again slightly pressing the polype with my forceps I cause the worm
partly to come out from its mouth, and thus draw out with it an equal
part of the end of its stomach. The worm, coming out of the mouth of
the polype, forces it to enlarge itself considerably, especially if it
comes out doubled up. When the polype is in this state, I take it
gently out of the water, without disturbing anything, and place it on
the edge of my hand, which is simply moistened, so that it may not
adhere too closely. I oblige it to contract more and more, and this
also enlarges the stomach and mouth. The worm then is partly coming
out of the mouth, and, keeping it open, I then take in my right hand
a hog's bristle, rather thick and without a point, and I hold it as
one holds a lancet for bleeding. I bring its thickest end to the hind
end of the polype and push it, making it enter into its stomach, which
is the more easily done as in that part it is empty and much enlarged.
I push on the end of