Manito eBooks

.............. 44
Length of longest cell above the
pulvinus...................................... 70
Seedling 13 days old, cotyledon 4.5 mm. in length, with a small true leaf
fully developed. Average length of cells of
pulvinus.................................................. 7
Length of longest cell below the
pulvinus..................................... 30
Length of longest cell above the
pulvinus...................................... 60
______________________________________
* Longitudinal sections show that the forms of the epidermic cells may be
taken as a fair representation of those constituting the pulvinus.
** Each division equalled .003 mm.
[page 121]
We here see that the cells of the pulvinus increase but little in length
with advancing age, in comparison with those of the petiole both above and
below it; but they continue to grow in width, and keep equal in this
respect with the other cells of the petiole. The rate of growth, however,
varies in all parts of the cotyledons, as may be observed in the
measurements of the 8-days' old seedling.


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