In another experiment a bud was split in two lengthwise, and the cut was
extended so that the body of the parent was separated into two pieces.
Twenty-four hours later it was found that each half-bud had closed in,
and was much larger than when first cut. The half-bud, that was attached
to the posterior end of the anterior piece, was constricting at its
base, and subsequently it separated at its point of attachment. The
other half of the bud, that had been left attached to the anterior end
of the posterior piece, had swung around, so that its long axis
corresponded to that of the posterior, parental piece. At first a slight
constriction indicated the line of union of the two, but later this
disappeared and a single hydra resulted. Whether the difference in the
fate of the two half-buds is connected with their different polar
relations to the parts of the parent, or is due to some other difference
in the absorbing power of the anterior and posterior pieces, is not
known.
[Illustration: FIG. 49.--After Peebles. _A._ Grafting in _Tubularia
mesenbryanthemum_. A small piece of the stock taken from the region near
the base, and grafted in a reversed direction on the oral end of a long
piece. _B._ Same with distal tentacles in small piece, and proximal
tentacles in large piece (modified from Peebles). _C._ Same. Formation
of hydranth (original). _D._ Like _A_. Both pieces produce hydranths.
_E._ Protrusion of hydranths of last. _F._ Piece of oral end cut off,
turned around and grafted on oral end of long piece. A single hydranth
produced. Distal tentacle from both components. _G_. A short piece from
distal (oral) end of long piece cut off, and grafted by its proximal end
to proximal end of the same long piece.]
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