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The next article is a review of Dr. Darwin's work on "The power of movement in plants." The apparatus which has been devised for the purpose, is minutely described, and is shown to be ingenious and simple, and handled with considerable skill. The conclusion which Darwin draws from the figures which through his apparatus the plant traces upon a chart, are very important. In the first place, he demonstrates, says the writer, from them, that all the growing parts of plants, whether connected with root stem or leaves, are unceasingly nodding round…They advance with a fitful and uncertain movement, suddenly jerking upwards and backwards, so that the actual track through space of any given point of the structure is an irregular ellipse, broken by zig-zags and minor curves, and continually changing both its form and place. Dr. Darwin has designated this fitful movement "circumnutation." The writer says that this circumnutating movement is manifestly controlled, and modified by the influence of light, of the alternation of darkness into light and of gravity; all of which combine to fix the precise line of the progress. We are told that "moisture exerts a considerable influence upon the course taken by the rootlet. The tip of a rootlet will even bend in antagonism to the pull of gravity, when the solicitation of moisture acts in another direction. Light influences the root in an exactly opposite way. The rootlet is stimulated to circumnutate away from any gleam of light that accidentally falls upon." Dr. Darwin seems to regard the tips of rootlets as possessing almost the attributes of a vegetable brain; but the difference between the movement of plants and that of animal protoplasms is that the former move or circumnutate because they grow, while the latter, the basement of animated flesh, moves because it is in process of combustive destruction, which is the exact opposite of elaborating construction.