the superincumbent fluid were placed on four leaves, and when these
were looked at after 16 hrs., the tentacles and blades of all were
found strongly inflected. I infer from a remark by Gerhardt* that
legumin is present in peas in combination with an alkali, forming an
incoagulable solution, and this would mingle with boiling water. I may
mention, in relation to the above and following experiments, that
according to Schiff** certain forms of albumen
* Watts Dictionary of Chemistry, vol. iii., p. 568.
** Lecons sur la Phys. de la Digestion, tom. i, p. 379; tom. ii. pp.
154, 166, on legumin. [page 83]
exist which are not coagulated by boiling water, but are converted into
soluble peptones.
On three occasions chopped cabbage-leaves* were boiled in distilled
water for 1 hr. or for 1 1/4 hr.; and by decanting the decoction after
it had been allowed to rest, a pale dirty green fluid was obtained. The
usual-sized drops were placed on thirteen leaves. Their tentacles and
blades were inflected after 4 hrs. to a quite extraordinary degree.
Next day the protoplasm within the cells of the tentacles was found
aggregated in the most strongly marked manner. I also touched the
viscid secretion round the glands of several tentacles with minute
drops of the decoction on the head of a small pin, and they became well
inflected in a few minutes. The fluid proving so powerful, one part was
diluted with three of water, and drops were placed on the discs of five
leaves; and these next morning were so much acted on that their blades
were completely doubled over. We thus see that a decoction of
cabbage-leaves is nearly or quite as potent as an infusion of raw meat.
About the same quantity of chopped cabbage-leaves and of distilled
water, as in the last experiment, were kept in a vessel for 20 hrs. in
a hot closet, but not heated to near the boiling-point. Drops of this
infusion were placed on four leaves. One of these, after 23 hrs., was
much inflected; a second slightly; a third had only the submarginal
tentacles inflected; and the fourth was not at all affected. The power
of this infusion is therefore very much less than that of the
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