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This chapter describes the circumnutating movements of young leaves in 33 genera, belonging to 25 families, widely distributed / among ordinary and gymnospermous Dicotyledons and among Monocotyledons, together with several Cryptogams. The extent of the movement differed much in different plants; but the distance passed over was never great, except with Pistia, which ought perhaps to have been included among sleeping plants. The oscillatory and jerking movements of the leaves of Dionaea, which resemble those of the hypocotyl of the cabbage, are highly remarkable, as seen under the microscope. The kind of movement in joints of certain Gramineae, and it is probably common to many plants while circumnutating. In only one genus, Cannabis did the leaves sink in the evening, and Kraus attributes this movement to the prepotency of their epinastic growth. Insectivorous plants are very little affected, their movements are concerned, by light; and hence probably it is that their leaves, in the case of Sarracenia, Drosera, and Dionaea.