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"The Movements and Habits of Climbing Plants," by Charles Darwin, M.A., F.R.S., is a book recording observations upon more than a hundred widely differing species, and showing that the young shoots of plants have powers of motion, and even of sensation. Occasional instances are familiar. The power of motion may be seen by any one who watches the unfolding of the night-blowing Ipomoea. About sunset these beautiful flowers burst open, and each may be observed even on the stillest evening to give a little jerk, as if to shake out the folds of their white robe; while the sensitive plant closes its leaves at the approach of a hand, and some insectivorous plants grasp their prey with all the appearance of avidity. There are four modes of climbing, which are distinguished as twining (of which the convovulus is an example). leaf-climbing (as the Monrundia), tendril-climbing (as the passion-flower), and root-climbing (ivy). Some plants make use of more than one mode of attaching themselves, while one Bignonia tweediana, combines all four. Two German botanists long ago discovered that the young shoots of all plants move after being shaken, and that the flower stalks of many, if shaken or slightly rubbed, turn to one side. All growing plants have a tendency to rotatory motion, sometimes in the direction of the sun, but more often in the opposite direction. These rudimentary powers have, in the case of climbers, become utilized and developed to enable them to rise into the free light and air. Mr. Darwin observed the rotatory motion of a plant belonging to the genus Ceropegia, which, sending out a shoot 31 inches in length, made a revolution of 16 feet four times during the 24 hours, travelling at the rate of 32 or 33 inches per hour. "The weather being hot," he says, "the plant was allowed to stand upon my study table, and it was an interesting spectacle to watch the long shoot sweeping this grand circle night and day in search of something round which to twine." The tendrils of plants are singularly sensitive. In one instance the touch of a pencil so gentle as only just to move the tendril borne at the end of a long flexible shoot was sufficient to cause it to become perceptibly curved in four or five minutes. We have ourselves tried this experiment upon the straight young tendril of a vine, and in eight minutes the curve was unmistakable. The experiment was tried about noon on a hot day. It really seems as if plants had some dawnings of intelligence, and Mr. Darwin's discoveries open a wide field for speculation.