temporary stomach, with the glands of the closely inflected tentacles
pouring forth their acid secretion, which dissolves animal matter,
afterwards to be absorbed, may be said to feed like an animal. But,
differently from an animal, it drinks by means of its roots; and it
must drink largely, so as to retain many drops of viscid fluid round
the glands, sometimes as many as 260, exposed during the whole day to a
glaring sun. [page 19]
CHAPTER II.
THE MOVEMENTS OF THE TENTACLES FROM THE CONTACT OF SOLID BODIES.
Inflection of the exterior tentacles owing to the glands of the disc
being excited by repeated touches, or by objects left in contact with
them Difference in the action of bodies yielding and not yielding
soluble nitrogenous matter Inflection of the exterior tentacles
directly caused by objects left in contact with their glands Periods of
commencing inflection and of subsequent re-expansion Extreme minuteness
of the particles causing inflection Action under water Inflection of
the exterior tentacles when their glands are excited by repeated
touches Falling drops of water do not cause inflection.
I will give in this and the following chapters some of the many
experiments made, which best illustrate the manner and rate of movement
of the tentacles, when excited in various ways. The glands alone in all
ordinary cases are susceptible to excitement. When excited, they do not
themselves move or change form, but transmit a motor impulse to the
bending part of their own and adjoining tentacles, and are thus carried
towards the centre of the leaf. Strictly speaking, the glands ought to
be called irritable, as the term sensitive generally implies
consciousness; but no one supposes that the Sensitive-plant is
conscious, and as I have found the term convenient, I shall use it
without scruple. I will commence with the movements of the exterior
tentacles, when indirectly excited by stimulants applied to the glands
of the short tentacles on the disc. The exterior tentacles may be said
in this case to be indirectly excited, because their own glands are not
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