found divided.
(2) After 4 hrs. 30 m. many of the tentacles at the distal end were
well inflected. Next day the blade and all the tentacles at this end
were strongly inflected, and were separated by a distinct transverse
line from the basal half of the leaf, which was not in the least
affected. On the third day, however, some of the short tentacles on the
disc near the base were very slightly inflected. The incision was found
on dissection to extend across the leaf as in the last case.
(3) After 4 hrs. 30 m. strong inflection of the tentacles at the distal
end, which during the next two days never extended in the least to the
basal end. The incision as before.
(4) This leaf was not observed until 15 hrs. had elapsed, and then all
the tentacles, except the extreme marginal ones, were found equally
well inflected all round the leaf. On careful examination the spiral
vessels of the central trunk were certainly divided; but the incision
on one side had not passed through the fibrous tissue surrounding these
vessels, though it had passed through the tissue on the other side.*]
The appearance presented by the leaves (2) and (3) was very curious,
and might be aptly compared with that of a man with his backbone broken
and lower extremities paralysed. Excepting that the line between the
two halves was here transverse instead of longitudinal, these leaves
were in the same state as some of those in the former experiments, with
bits of meat placed on one side of the disc. The case of leaf (4)
* M. Ziegler made similar experiments by cutting the spiral vessels of
Drosera intermedia( Comptes rendus, 1874, p. 1417), but arrived at
conclusions widely different from mine. [page 250]
proves that the spiral vessels of the central trunk may be divided, and
yet the motor impulse be transmitted from the distal to the basal end;
and this led me at first to suppose that the motor force was sent
through the closely surrounding fibrous tissue; and that if one half of
this tissue was left undivided, it sufficed for complete transmission.
But opposed to this conclusion is the fact that no vessels pass
directly from one side of the leaf to the other, and yet, as we have
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