The ellipses described by Lathyrus nissolia and
Brassica were narrow, whilst those made by the Oak were broad. The figures
are often complicated by small loops and zigzag lines.
As most seedling plants before the development of true leaves are of low,
sometimes very low stature,
[page 108]
the extreme amount of movement from side to side of their circumnutating
stems was small; that of the hypocotyl of Githago segetum was about .2 of
an inch, and that of Cucurbita ovifera about .28. A very young shoot of
Lathyrus nissolia moved about .14, that of an American oak .2, that of the
common nut only .04, and a rather tall shoot of the Asparagus .11 of an
inch. The extreme amount of movement of the sheath-like cotyledon of
Phalaris Canariensis was .3 of an inch; but it did not move very quickly,
the tip crossing on one occasion five divisions of the micrometer, that is,
1/100th of an inch, in 22 m. 5 s. A seedling Nolana prostrata travelled the
same distance in 10 m. 38 s. Seedling cabbages circumnutate much more
quickly, for the tip of a cotyledon crossed 1/100th of an inch on the
micrometer in 3 m.
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