SPONTANEOUS MOVEMENTS IN PLANTS. 
375 
to credit the statement of Mr. Anderson-Henry that a climber 
will, in running up a wall, carefully avoid contact with another 
climber which it dislikes ; and even the account by M. Paul 
Levy * that the Hanes of tropical forests have an affinity for 
certain trees, towards which they direct their growth, and not 
towards those nearest to them ; carefully drawing themselves 
away when they encounter one of the objectionable trees. 
We may conclude our account of climbing plants with the 
following remarks by Mr. Darwin : — “ 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 advan- 
tage to them, but that this is of comparatively rare occurrence, 
as they are affixed to the ground and food is brought to them 
by the wind and rain. We see how high in the scale of or- 
ganisation 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 
itself. 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. In the course of 
some hours it contracts into a spire, dragging up the stem, and 
forming an excellent spring. All movements now cease. By 
growth, the tissues become wonderfully strong and durable. 
The tendril has done its work, and done it in an admirable 
manner.” 
The phenomenon known as Sensitiveness is of by no means 
uncommon occurrence in the vegetable kingdom. It consists 
of a sudden movement of the leaf, a portion of the flower, or 
the whole plant, on contact with, or even on the approach of, a 
foreign body. One of the most familiar examples is that of 
the Sensitive Plant, Mimosa pudica and sensitiva , fig. 1 , a 
and 6, in which three distinct movements are observable when 
the leaf is touched by the hand or the warm breath. First, 
the numerous leaflets close in pairs, bringing their upper faces 
together, and also inclining forwards ; then the four branches 
of the leaf-stalk, which were outspread like the rays of a fan, 
approach each other; at the same time the main leaf-stalk 
turns downwards, bending at its joint with the stem. The ex- 
planation offered in one of our best botanical text-books of this 
phenomenon is as follows : — “ There is a swelling at the base 
* Bulletin de la Societe Botanique de France. Translated in tlie 11 Gar** 
flener’s Chronicle,” March 19, 1870. 
