We made no observations on the movements of the different parts of flowers. Morren, however, has observed[7] in the stamens of Sparmannia and Cereus a “fremissement spontané,” which, it may be suspected, is a circumnutating movement. The circumnutation of the gynostemium of Stylidium, as described by Gad,[8] is highly remarkable, and apparently aids in the fertilisation of the flowers. The gynostemium, whilst spontaneously moving, comes into contact with the viscid labellum, to which it adheres, until freed by the increasing tension of the parts or by being touched. [7] ‘N. Mem. de l’Acad. R. de Bruxelles,’ tom. xiv. 1841, p. 3. [8] ‘Sitzungbericht des bot. Vereins der P. Brandenburg,’ xxi. p. 84. We have now seen that the flower-stems of plants belonging to such widely different families as the Cruciferae, Oxalidæ, Leguminosae, Primulaceae, Scrophularineae, Alismaceae, and Liliaceae, circumnutate; and that there are indications of this movement in many other families. With these facts before us, bearing also in mind that the tendrils of not a few plants consist of modified peduncles, we may admit without much doubt that all growing flower-stems circumnutate. CIRCUMNUTATION OF LEAVES: DICOTYLEDONS. Several distinguished botanists, Hofmeister, Sachs, Pfeffer, De Vries, Batalin, Millardet, etc., have observed, and some of them with the greatest care, the periodical movements of leaves; but their attention has been chiefly, though not exclusively, directed to those which move largely and are commonly said to sleep at night. From considerations hereafter to be given, plants of this nature are here excluded, and will be treated of separately. As we wished to ascertain whether all young and growing leaves circumnutated, we thought that it would be sufficient if we observed between 30 and 40 genera, widely distributed throughout the vegetable series, selecting some unusual forms and others on woody plants. All the plants were healthy and grew in pots. They were illuminated from above, but the light perhaps was not always sufficiently bright, as many of them were observed under a skylight of ground-glass. Except in a few specified cases, a fine glass filament with two minute triangles of paper was fixed to the leaves, and their movements were traced on a vertical glass (when not stated to the contrary) in the manner already described. I may repeat that the broken lines represent the nocturnal course. The stem was always secured to a stick, close to the base of the leaf under observation. The arrangement of the species, with the number of the Family appended, is the same as in the case of stems. Fig. 93. Sarracenia purpurea: circumnutation of young pitcher, traced from 8 A.M. July 3rd to 10.15 A.M. 4th. Temp. 17°–18° C. Apex of pitcher 20 inches from glass, so movement greatly magnified.