in the usual manner. The tracing here given (Fig. 47)
indicates circumnutation. The movement of the upper part above the knee of
the same cotyledon, which projected at about an angle of 45o above the
horizon, was observed at the same time. A filament was not affixed to it,
but a mark was placed beneath the apex, which was almost white from
beginning to wither, and its movements were thus traced. The figure
described resembled pretty closely that above given; and this shows that
the chief seat of movement is in the lower or basal part of the cotyledon.
Fig. 47. Allium cepa: circumnutation of basal half of arched cotyledon,
traced in darkness on horizontal glass, from 8.15 A.M. to 10 P.M. Oct.
31st. Movement of bead magnified about 17 times.
Asparagus officinalis (Asparageae).--The tip of a straight plumule or
cotyledon (for we do not know which it should be called) was found at a
depth of .1 inch beneath the surface, and the earth was then removed all
round to the dept of .3 inch. a glass filament was affixed obliquely to it,
and the movement of the bead, magnified 17 times, was traced in darkness.
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