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A NEW book by Mr Darwin is something to brighten the dark days of December, and inspire students with warmth as they pore over his propositions and conclusions. As the title –The Power of Movement in Plants -implies, the eminent naturalist and philosopher has been working once more in the borderland between the animal and the vegetable worlds, and now he makes known how much they have in common. But his chief object, as he explains, 'is to describe and connect together several large classes of movement, common to almost all plants. The most widely prevalent movement is essentially of the same nature as that of the stem of a climbing plant, which bends successively to all points of the compass, so that the tip revolves.' The methods of observation were singularly delicate and ingenious so that even the movements of the radicles of seeds could be noted. Certain plants which fold their leaves together at night, and, familiarly speaking, go to sleep, were prevented by pinning the leaves out horizontally: the leaves thus treated were killed by frost, while similar plants left to fold their leaves in the natural way were not killed. The effects of light, of touch, and of other  influences, as described in this interesting volume, seem wonderful: especially remarkable is the sensitiveness of the tip of the radicle, which detects light, moisture, hardness, and softness, and behaves accordingly.

In Mr Darwin's words: 'It is hardly an exaggeration to say that the tip of the radicle thus endowed, and having the power of directing the movements of the adjoining parts, acts like the brain of one of the lower animals; the brain being seated within the anterior end of the body,

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receiving impressions from the sense-organs, and directing the several movements.'