three days and a half within, and the bladders were then cut open; but
none of the above substances exhibited the least signs of digestion or
dissolution; the angles of the cubes being as sharp as ever. These
observations were made subsequently to those on Drosera, Dionaea,
Drosophyllum, and Pinguicula; so that I was familiar with the
appearance of these substances when undergoing the early and final
stages of digestion. We may therefore conclude that Utricularia cannot
digest the animals which it habitually captures.
In most of the bladders the captured animals are so much decayed that
they form a pale brown, pulpy mass, with their chitinous coats so
tender that they fall to pieces with the greatest ease. The black
pigment of the eye-spots is preserved better than anything else. Limbs,
jaws, &c. are often found quite detached; and this I suppose is the
result of the vain struggles of the later captured animals. I have
sometimes felt surprised at the small proportion of imprisoned animals
in a fresh state compared with those utterly decayed. Mrs. Treat states
with respect [page 411] to the larv above referred to, that usually
in less than two days after a large one was captured the fluid contents
of the bladders began to assume a cloudy or muddy appearance, and often
became so dense that the outline of the animal was lost to view. This
statement raises the suspicion that the bladders secrete some ferment
hastening the process of decay. There is no inherent improbability in
this supposition, considering that meat soaked for ten minutes in water
mingled with the milky juice of the papaw becomes quite tender and soon
passes, as Browne remarks in his Natural History of Jamaica, into a
state of putridity.
Whether or not the decay of the imprisoned animals is an any way
hastened, it is certain that matter is absorbed from them by the
quadrifid and bifid processes. The extremely delicate nature of the
membrane of which these processes are formed, and the large surface
which they expose, owing to their number crowded over the whole
interior of the bladder, are circumstances all favouring the process of
absorption. Many perfectly clean bladders which had never caught any
prey were opened, and nothing could be distinguished with a No. 8
object-glass of Hartnack within the delicate, structureless
protoplasmic lining of the arms, excepting in each a single yellowish
particle or modified nucleus. Sometimes two or even three such
particles were present; but in this case traces of decaying matter
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