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Updated: May 10, 2025
The function of the endosperm is primarily that of nourishing the embryo, and its basal position in the embryo-sac places it favourably for the absorption of food material entering the ovule. Its duration varies with the precocity of the embryo.
Granting that the assumption of Darwinism rests, as claimed, on the fixed and inflexible adaptation of means to ends, in the diversified yet measurably specialized processes of nature, there is no logical deduction to be drawn therefrom but that which traces the representatives of all the great types of the animal kingdom to one single source, and that not the Sovereign Intelligence of the Universe, but a mere "ovule in protoplasm," or what may be defined, in its unaggregated form, as an inconceivably small whirligig, having motion on a central axis, but whether an independent motion of its own, or one derived from an Infinite Intelligence, the Darwinian systematizers are not bold enough to aver.
And when a pollen grain lands on a pistil and joins with the ovule prepared in the ovary, the two components are united again. Out of the now complete seed a new and complete plant can arise. Goethe understood that he would be taught a correct conception of this process only by the plant itself.
The development of the ovule, which represents the macrosporangium, is very similar to the process in Gymnosperms; when mature it consists of one or two coats surrounding the central nucellus, except at the apex where an opening, the micropyle, is left. The nucellus is a cellular tissue enveloping one large cell, the embryo-sac or macrospore.
Lastly, when the pollen crept in at the tiny opening we learnt that the ovule had now all it wanted to grow into a perfect seed. And so we came back to a primrose seed, the point from which we started; and we have a history of our primrose from its birth to the day when its leaves and flowers wither away and it dies down for the winter. But what fairies are they which have been at work here?
Darwin, of plants which are more fertile with the pollen of another species than with their own; and there are others, such as certain Fuci, the male element of which will fertilise the ovule of a plant of distinct species, while the males of the latter species are ineffective with the females of the first.
Careful examination further proves that the whole substance of the nettle is made up of a repetition of such masses of nucleated protoplasm, each contained in a wooden case, which is modified in form, sometimes into a woody fibre, sometimes into a duct or spiral vessel, sometimes into a pollen grain, or an ovule.
Darwin, of plants which are more fertile with the pollen of another species than with their own; and there are others, such as certain fuci, whose male element will fertilize the ovule of a plant of distinct species, while the males of the latter species are ineffective with the females of the first.
The spermatozoon penetrates into the ovule and becomes fused with it. The processes of development begin at once to occur. There is congestion of the uterine mucous membrane out of proportion to the rest of the uterus; the ovum finds lodging here, and becomes surrounded by a membrane which incloses it in a separate sac. Pregnancy Defined.
When placed on the stigma, under favourable circumstances, the pollen-grain puts forth a pollen-tube which grows down the tissue of the style to the ovary, and makes its way along the placenta, guided by projections or hairs, to the mouth of an ovule.
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