FIG. 18. (Utricularia neglecta.) Bladder; much enlarged. c, collar
indistinctly seen through the walls.
plants for me in a state of nature, and found this commonly to be the
case, but the younger bladders often had their valves turned upwards.
The general appearance of a bladder viewed laterally, with the
appendages on the near side alone represented, is shown in the
accompanying figure (fig. 18). The lower side, where the footstalk
arises, is nearly straight, and I have called it the ventral surface.
The other or dorsal surface is convex, and terminates in two long
prolongations, formed of several rows of cells, containing chlorophyll,
and bearing, chiefly on [page 399] the outside, six or seven long,
pointed, multicellular bristles. These prolongations of the bladder may
be conveniently called the antenn , for the whole bladder (see fig. 17)
curiously resembles an entomostracan crustacean, the short footstalk
representing the tail. In fig. 18, the near antenna alone is shown.
Beneath the two antenn the end of the bladder is slightly truncated,
and here is situated the most important part of the whole structure,
namely the entrance and valve. On each side of the entrance from three
to rarely seven long, multicellular bristles project out-
FIG. 19. (Utricularia neglecta.) Valve of bladder; greatly enlarged.
wards; but only those (four in number) on the near side are shown in
the drawing. These bristles, together with those borne by the antenn ,
form a sort of hollow cone surrounding the entrance.
The valve slopes into the cavity of the bladder, or upwards in fig. 18.
It is attached on all sides to the bladder, excepting by its posterior
margin, or the lower one in fig. 19, which is free, and forms one side
of the slit-like orifice leading into the bladder. This margin is
sharp, thin, and smooth, and rests on the edge of a rim or collar,
which dips deeply into the [page 400] bladder, as shown in the
longitudinal section (fig. 20) of the collar and valve; it is also
shown at c, in fig. 18. The edge of the valve can thus open only
inwards. As both the valve and collar dip into the bladder, a hollow or
depression is here formed, at the base of which lies the slit-like
orifice.
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