After an interval of 72 hrs., from the time when the five cubes were
placed on the leaves, I opened the four remaining ones. On two nothing
could be seen but little masses of transparent viscid fluid; but when
these were examined under a high power, fat-globules, bits of
fibro-elastic tissue, and some few parallelograms of sarcous matter,
could be distinguished, but not a vestige of transverse striae. On the
other two leaves there were minute spheres of only partially digested
meat in the centre of much transparent fluid.
Fibrin.—Bits of fibrin were left in water during four days, whilst the
following experiments were tried, but they were not in the least acted
on. The fibrin which I first used was not pure, and included dark
particles: it had either not been well prepared or had subsequently
undergone some change. Thin portions, about 1/10 of an inch square,
were placed on several leaves, and though the fibrin was soon
liquefied, the whole was never dissolved. Smaller particles were then
placed on four leaves, and minute [page 101] drops of hydrochloric acid
(one part to 437 of water) were added; this seemed to hasten the
process of digestion, for on one leaf all was liquified and absorbed
after 20 hrs.; but on the three other leaves some undissolved residue
was left after 48 hrs. It is remarkable that in all the above and
following experiments, as well as when much larger bits of fibrin were
used, the leaves were very little excited; and it was sometimes
necessary to add a little saliva to induce complete inflection. The
leaves, moreover, began to re-expand after only 48 hrs., whereas they
would have remained inflected for a much longer time had insects, meat,
cartilage, albumen, &c., been placed on them.
I then tried some pure white fibrin, sent me by Dr. Burdon Sanderson.
[Experiment 1.—Two particles, barely 1/20 of an inch (1.27 mm.) square,
were placed on opposite sides of the same leaf. One of these did not
excite the surrounding tentacles, and the gland on which it rested soon
dried. The other particle caused a few of the short adjoining tentacles
to be inflected, the more distant ones not being affected. After 24
hrs. both were almost, and after 72 hrs. completely, dissolved.
Experiment 2.—The same experiment with the same result, only one of the
two bits of fibrin exciting the short surrounding tentacles. This bit
was so slowly acted on that after a day I pushed it on to some fresh
glands. In three days from the time when it was first placed on the
leaf it was completely dissolved.
Experiment 3.—Bits of fibrin of about the same size as before were
placed on the discs of two leaves; these caused very little inflection
in 23 hrs., but after 48 hrs. both were well clasped by the surrounding
short tentacles, and after an additional 24 hrs. were completely
dissolved. On the disc of one of these leaves much clear acid fluid was
left.