the same time would have been dissolved by the secretion from several
of the small sessile glands. Owing to the death of my last plant, I was
unable to ascertain which of these alternatives is the true one.
Four minute shreds of pure fibrin were placed, each resting on one,
two, or three of the taller glands. In the course of 2 hrs. 30 m. the
secretion was all absorbed, and the shreds were left almost dry. They
[page 341] were then pushed on to the sessile glands. One shred, after
2 hrs. 30 m., seemed quite dissolved, but this may have been a mistake.
A second, when examined after 17 hrs. 25 m., was liquefied, but the
liquid as seen under the microscope still contained floating granules
of fibrin. The other two shreds were completely liquefied after 21 hrs.
30 m.; but in one of the drops a very few granules could still be
detected. These, however, were dissolved after an additional interval
of 6 hrs. 30 m.; and the surface of the leaf for some distance all
round was covered with limpid fluid. It thus appears that Drosophyllum
digests albumen and fibrin rather more quickly than Drosera can; and
this may perhaps be attributed to the acid, together probably with some
small amount of the ferment, being present in the secretion, before the
glands have been stimulated; so that digestion begins at once.
Concluding Remarks.—The linear leaves of Drosophyllum differ but
slightly from those of certain species of Drosera; the chief
differences being, firstly, the presence of minute, almost sessile,
glands, which, like those of Dionaea, do not secrete until they are
excited by the absorption of nitrogenous matter. But glands of this
kind are present on the leaves of Drosera binata, and appear to be
represented by the papillae on the leaves of Drosera rotundifolia.
Secondly, the presence of tentacles on the backs of the leaves; but we
have seen that a few tentacles, irregularly placed and tending towards
abortion, are retained on the backs of the leaves of Drosera binata.
There are greater differences in function between the two genera. The
most important one is that the tentacles of Drosophyllum have no power
of movement; this loss being partially replaced by the drops of viscid
[page 342] secretion being readily withdrawn from the glands; so that,
when an insect comes into contact with a drop, it is able to crawl
away, but soon touches other drops, and then, smothered by the
secretion, sinks down on the sessile glands and dies. Another
difference is, that the secretion from the tall glands, before they
have been in any way excited, is strongly acid, and perhaps contains a
small quantity of the proper ferment. Again, these glands do not
secrete more copiously from being excited by the absorption of
nitrogenous matter; on the contrary, they then absorb their own
secretion with extraordinary quickness. In a short time they begin to
secrete again. All these circumstances are probably connected with the
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