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214
drawings of the ovary given by BAILLON and ENGLER-PRANTL and
referring to S. Soda and Kali respectively do not agree with my
sections of S. Kali. There is, in fact, much less space within the
ovary, so that the young ovule seems really to be in contact with
the wall on the tetrade stage, at the latest. From the tetrade stage
until fertilization, the ovule is very irregularly sited, more or less
bended over. The shape of the ovary cavity all the time closely
following the outlines of the ovule, it is impossible to say, if the
bending-over ovule determines the shape of the cavity, or the reverse.
But after fertilization the ovary rapidly grows broader and flatter,
its cavity, from the beginning rounded and higher than its width,
becomes a low funnelshaped, and the ovule at the same time com-
pletely bends down so as to reach a transversal position (d in
figure 1). In this later developement, the ovary seems to be the lead-
ding part, at least its upper edge growing out actively without any
pressure from the ovule.
To elucidate the matter I have investigated a number of ripe
seeds. In 56 investigated seeds the embryo always, conformingly
to the description by HEGELMAIER, lies so as to turn the base of the
cochlea with the root end versus the apex of the ovary. But the
spiral formed by root and axis organ is 24 times right, 32 times
left winding, that makes 43%-+-6,7% right winding, the probable error
indicated. The embryo winds then as often to the right as to the
left. This result seems to indicate that external agents rather than
internal formative factors are responsible already for the first ben-
ding-over of the ovule and, thus, for the final shape of the embryo.
LITERATURE CITED.
BAILLON, Historie des plantes. — Tome IX, p. 142, fig. 195.
ENGLER-PRANTL, Die natürlichen Pflanzenfamilien. — Bd III, 1 a, p. 84.
HEGELMAIER, Untersuchungen über die Morphologie des Dikotyledonen-
Endosperms. — Nova Acta d. kais. Leop.-Carol. deutsch. Akad. d. Na-
turf., Bd. 49, N:r 1, Halle 1885.
MEUNIER, Les téguments sémineaux des Cyclospermes. — La Cellule 6, 1890.
TIEGHEM, VAN, Traité de botanique. — Paris 1884.
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