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This is one of the most remarkable plants in cultivation. The sensitiveness to touch of Mimosa pudica, Dionæa, &c., is singular enough, but the movements of the leaves of this Desmodium seem still more curious, and up to the present have baffled our best observers. Darwin, in his recently published work on "The Power of Movement in Plants," gives the results of his experiments on this Desmodium and other plants, by which he has succeeded improving that in all plants there is a power which causes them to move in a rotatory direction, or, as he terms it, to circumnutate. This movement he explains as being of some importance, as an aid to the growth and protection of the plant, but as to the movements of this Desmodium he says, "No one supposes that the rapid movements of the lateral leaflets of D. gyrans are of any use to the plant, and why they should behave in this manner is quite unknown." The movement may be best observed on a light warm day, when the plant is standing in a

[Figure] Telegraph Plant (Desmodium gyrans).

temperature of about 80°. The two small lateral leaflets may then be observed to move upwards and downwards, first the one and then the other, now resting a moment, then starting again with a jerk. The movement is quite spontaneous, the plant not being perceptibly sensitive to the touch. Truly it is a vegetable wonder, and deserves a place in every stove on that account. It is easily propagated either by means of seeds or cuttings. It is a rapid grower, and, though it is not handsome, still it is a graceful plant. It grows to a height of about 2ft. Any light soil twill suit it, and the higher the temperature in which it stands the more perceptible are its movements. I do not think it would thrive in winter in a temperature lower than 55°. It is a native of India, and is a member of the Leguminous (Pea) family.

Z. B.