The stem, however, cannot twine, but ascends an
upright stick by seizing it above with both tendrils together, which
then contract into a spire. The tips of these tendrils become
developed into adhesive discs. B. speciosa possesses similar powers
of movement as the last species, but it cannot twine round a stick,
though it can ascend by clasping the stick horizontally with one or
both of its unbranched tendrils. These tendrils continually insert
their pointed ends into minute crevices or holes, but as they are
always withdrawn by the subsequent spiral contraction, the habit
seems to us in our ignorance useless. Lastly, the stem of B.
capreolata twines imperfectly; the much-branched tendrils revolve in
a capricious manner, and bend from the light to the dark; their
hooked extremities, even whilst immature, crawl into crevices, and,
when mature, seize any thin projecting point; in either case they
develop adhesive discs, and these have the power of enveloping the
finest fibres.
In the allied Eccremocarpus the internodes, petioles, and much-
branched tendrils all spontaneously revolve together. The tendrils
do not as a whole turn from the light; but their bluntly-hooked
extremities arrange themselves neatly on any surface with which they
come into contact, apparently so as to avoid the light.
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