Nevertheless, on the following night they rose as usual.
Cytisus fragrans (Leguminosae).--Only a few observations were made on this
plant. The hypocotyl circumnutated to a considerable extent, but in a
simple manner--namely, for two hours in one direction, and then much more
slowly back again in a zigzag course, almost parallel to the first line,
and beyond the starting-point. It moved in the same direction all night,
but next morning began to return. The cotyledons continually
[page 38]
move both up and down and laterally; but they do not rise up at night in a
conspicuous manner.
Lupinus luteus (Leguminosae).--Seedlings of this plant were observed
because the cotyledons are so thick (about .08 of an inch) that it seemed
unlikely that they would move. Our observations were not very successful,
as the seedlings are strongly heliotropic, and their circumnutation could
not be accurately observed near a north-east window, although they had been
kept during the previous day in the same position. A seedling was then
placed in darkness with the hypocotyl secured to a stick; both cotyledons
rose a little at first, and then fell during the rest of the day; in the
evening between 5 and 6 P.
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