Cucurbita aurantia.—An arched hypocotyl was found buried a little beneath the surface of the soil; and in order to prevent it straightening itself quickly, when relieved from the surrounding pressure of the soil, the two legs of the arch were tied together. The seed was then lightly covered with loose damp earth. A filament with a bead at the end was affixed to the basal leg, the movements of which were observed during two days in the usual manner. On the first day the arch moved in a zigzag line towards the side of the basal leg. On the next day, by which time the dependent cotyledons had been dragged above the surface of the soil, the tied arch changed its course greatly nine times in the course of 14½ h. It swept a large, extremely irregular, circular figure, returning at night to nearly the same spot whence it had started early in the morning. The line was so strongly zigzag that it apparently represented five ellipses, with their longer axes pointing in various directions. With respect to the periodical movements of the cotyledons, those of several young seedlings formed together at 4 P.M. an angle of about 60°, and at 10 P.M. their lower parts stood vertically and were in contact; their tips, however, as is usual in the genus, were permanently reflexed. These cotyledons, at 7 A.M. on the following morning, were again well expanded. Lagenaria vulgaris (var. miniature Bottle-gourd) (Cucurbitaceæ).—A seedling opened its cotyledons, the movements of which were alone observed, slightly on June 27th and closed them at night: next day, at noon (28th), they included an angle of 53°, and at 10 P.M. they were in close contact, so that each had risen 26½°. At noon, on the 29th, they included an angle of 118°, and at 10 P.M. an angle of 54°, so each had risen 32°. On the following day they were still more open, and the nocturnal rise was greater, but the angles were not measured. Two other seedlings were observed, and behaved during three days in a closely similar manner. The cotyledons, therefore, open more and more on each succeeding day, and rise each night about 30°; consequently during the first two nights of their life they stand vertically and come into contact. Fig. 30. Lagenaria vulgaris: circumnutation of a cotyledon, 1½ inch in length, apex only 4 3/4 inches from the vertical glass, on which its movements were traced from 7.35 A.M. July 11th to 9.5 A.M. on the 14th. Figure here given reduced to one-third of original scale.