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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 14 ? 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 60o, 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) (Cucurbitaceae).--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 53o, and at 10 P.


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