The antenn are of moderate length, and taper to a fine point; they
differ conspicuously from those before described, in not being armed
with bristles. Their bases are so abruptly curved that their tips
generally rest one on each side of the middle of the bladder, but
FIG. 27. (Utricularia montana.) Bladder; about 27 times enlarged.
sometimes near the margin. Their curved bases thus form a roof over the
cavity in which the valve lies; but there is always left on each side a
little circular passage into the cavity, as may be seen in the drawing,
as well as a narrow passage between the bases of the two antenn . As
the bladders are subterranean, had it not been for the roof, the cavity
in which the valve lies would have been liable to be blocked up with
earth [page 434] and rubbish; so that the curvature of the antenn is a
serviceable character. There are no bristles on the outside of the
collar or peristome, as in the foregoing species.
The valve is small and steeply inclined, with its free posterior edge
abutting against a semicircular, deeply depending collar. It is
moderately transparent, and bears two pairs of short stiff bristles, in
the same position as in the other species. The presence of these four
bristles, in contrast with the absence of those on the antenn and
collar, indicates that they are of functional importance, namely, as I
believe, to prevent too large animals forcing an entrance through the
valve. The many glands of diverse shapes attached to the valve and
round the collar in the previous species are here absent, with the
exception of about a dozen of the two-armed or transversely elongated
kind, which are seated near the borders of the valve, and are mounted
on very short footstalks. These glands are only the 3/4000 of an inch
(.019 mm.) in length; though so small, they act as absorbents. The
collar is thick, stiff, and almost semi-circular; it is formed of the
same peculiar brownish tissue as in the former species.
The bladders are filled with water, and sometimes include bubbles of
air. They bear internally rather short, thick, quadrifid processes
arranged in approximately concentric rows. The two pairs of arms of
which they are formed differ only a little in length, and stand in a
peculiar position (fig. 28); the two longer ones forming one line, and
the two shorter ones another parallel line. Each arm includes a small
spherical mass of brownish matter, which, when crushed, breaks into
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