processes did not appear more aggregated than in other speci- [page
301] mens kept in water, I then tried suspending a leaf in a bottle
over an excessively putrid infusion of raw meat, to see whether they
absorbed the vapour, but their contents were not affected.
Digestive Power of the Secretion.* When a leaf closes over any object,
it may be said to form itself into a temporary stomach; and if the
object yields ever so little animal matter, this serves, to use
Schiff s expression, as a peptogene, and the glands on the surface pour
forth their acid secretion, which acts like the gastric juice of
animals. As so many experiments were tried on the digestive power of
Drosera, only a few were made with Dionaea, but they were amply
sufficient to prove that it digests, This plant, moreover, is not so
well fitted as Drosera for observation, as the process goes on within
the closed lobes. Insects, even beetles, after being subjected to the
secretion for several days, are surprisingly softened, though their
chitinous coats are not corroded,
[Experiment 1. A cube of albumen of 1/10 of an inch (2.540 mm.) was
placed at one end of a leaf, and at the other end an oblong piece of
gelatine, 1/5 of an inch (5.08 mm.) long, and
* Dr. W.M. Canby, of Wilmington, to whom I am much indebted for
information regarding Dionaea in its native home, has published in the
Gardener s Monthly, Philadelphia, August 1868, some interesting
observations. He ascertained that the secretion digests animal matter,
such as the contents of insects, bits of meat, &c.; and that the
secretion is reabsorbed. He was also well aware that the lobes remain
closed for a much longer time when in contact with animal matter than
when made to shut by a mere touch, or over objects not yielding soluble
nutriment; and that in these latter cases the glands do not secrete.
The Rev. Dr. Curtis first observed ( Boston Journal Nat. Hist. vol.
i., p. 123) the secretion from the glands. I may here add that a
gardener, Mr. Knight, is said (Kirby and Spencer s Introduction to
Entomology, 1818, vol. i., p. 295) to have found that a plant of the
Dionaea, on the leaves of which he laid fine filaments of raw beef,
was much more luxuriant in its growth than others not so treated.
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