bifid processes; and on the view above maintained, namely that they
absorb matter from putrid water occasionally emitted from the bladders,
they ought to act more quickly than the processes; as these latter
remain in permanent contact with captured and decaying animals.
Finally, the conclusion to which we are led by the foregoing
experiments and observations is that the bladders have no power of
digesting animal matter, though it appears that the quadrifids are
somewhat affected by a fresh infusion of raw meat. It is certain that
the processes within the bladders, and the glands outside, absorb
matter from salts of [page 424] ammonia, from a putrid infusion of raw
meat, and from urea. The glands apparently are acted on more strongly
by a solution of urea, and less strongly by an infusion of raw meat,
than are the processes. The case of urea is particularly interesting,
because we have seen that it produces no effect on Drosera, the leaves
of which are adapted to digest fresh animal matter. But the most
important fact of all is, that in the present and following species the
quadrifid and bifid processes of bladders containing decayed animals
generally include little masses of spontaneously moving protoplasm;
whilst such masses are never seen in perfectly clean bladders.
Development of the Bladders. My son and I spent much time over this
subject with small success. Our observations apply to the present
species and to Utricularia vulgaris, but were made chiefly on the
latter, as the bladders are twice as large as those of Utricularia
neglecta. In the early part of autumn the stems terminate in large
buds, which fall off and lie dormant during the winter at the bottom.
The young leaves forming these buds bear bladders in various stages of
early development. When the bladders of Utricularia vulgaris are about
1/100 inch (.254 mm.) in diameter (or 1/200 in the case of Utricularia
neglecta), they are circular in outline, with a narrow, almost closed,
transverse orifice, leading into a hollow filled with water; but the
bladders are hollow when much under 1/100 of an inch in diameter. The
orifices face inwards or towards the axis of the plant. At this early
age the bladders are flattened in the plane in which the orifice lies,
and therefore at right angles to that of the mature bladders. They are
covered exteriorly with papillae of different sizes, many of which have
an elliptical outline. A bundle of vessels, formed of [page 425] simple
elongated cells, runs up the short footstalk, and divides at the base
of the bladder. One branch extends up the middle of the dorsal surface,
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