, species in only two or three genera
have the power of climbing, the conclusion is forced on our minds
that the capacity of revolving, on which most climbers depend, is
inherent, though undeveloped, in almost every plant in the vegetable
kingdom.
It has often been vaguely asserted that plants are distinguished from
animals by not having the power of movement. It should rather be
said that plants acquire and display this power only when it is of
some advantage to them; this being of comparatively rare occurrence,
as they are affixed to the ground, and food is brought to them by the
air and rain. We see how high in the scale of organization a plant
may rise, when we look at one of the more perfect tendril-bearers.
It first places its tendrils ready for action, as a polypus places
its tentacula. If the tendril be displaced, it is acted on by the
force of gravity and rights it self. It is acted on by the light,
and bends towards or from it, or disregards it, whichever may be most
advantageous. During several days the tendrils or internodes, or
both, spontaneously revolve with a steady motion. The tendril
strikes some object, and quickly curls round and firmly grasps it.
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