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The colour was caused by little gelatinous balls, about the fifth of an inch in diameter, in which numerous minute spherical ovules were embedded: they were of two distinct kinds, one being of a reddish colour and of a different shape from the other. I cannot form a conjecture as to what two kinds of animals these belonged.
The ovules of plants after fertilisation have to be nourished for a time; hence the pollen is necessarily brought to the female organs being placed on the stigma, by means of insects or the wind, or by the spontaneous movements of the stamens; and in the Algae, etc., by the locomotive power of the antherozooids.
Here the floriated thyrsus, there a lance-head, farther on Egyptian urns, now and then a few cannon; on all sides the emblems of professions, and every style of art, Moorish, Greek, Gothic, friezes, ovules, paintings, vases, guardian-angels, temples, together with innumerable immortelles, and dead rose-bushes. It is a forlorn comedy!
In certain whole groups of plants the ovules stand erect, and in others they are suspended; and within the same ovarium of some few plants, one ovule holds the former and a second ovule the latter position. These positions seem at first purely morphological, or of no physiological signification; but Dr.
From the inside of each ovary the tiny eggs, or ova, grow, just as the ovules grow in the plant ovary or seed-pod. At first they are a part of the ovary; later they grow larger and fall loose, until the ovary is filled with them. The ovary is always inside the fish. It is there when the fish is born, and even then there are the tiniest hints of ova in it.
If so, the position of the ovules, even when one is erect and the other suspended within the same ovarium, would follow the selection of any slight deviations in position which favoured their fertilisation, and the production of seed. Several plants belonging to distinct orders habitually produce flowers of two kinds the one open, of the ordinary structure, the other closed and imperfect.
Look at the pod against the light and see the ovules dimly outlined. Each ovule is attached to the pod by a little stem which can also be seen with the light shining through the pod. The stem the child can look for when the peas are being shelled for dinner, or when lima beans are being shelled.
If we admire the several ingenious contrivances by which orchids and many other plants are fertilised through insect agency, can we consider as equally perfect the elaboration of dense clouds of pollen by our fir-trees, so that a few granules may be wafted by chance on to the ovules? We have in this chapter discussed some of the difficulties and objections which may be urged against the theory.
He specifies the arrangement of the cells in the tissues, and of the leaves on the axis, as cases in which natural selection could not have acted. To these may be added the numerical divisions in the parts of the flower, the position of the ovules, the shape of the seed, when not of any use for dissemination, etc. There is much force in the above objection.
The fertilisation of the ovules by pollen which falls directly from the anthers on to the stigma can be used as a representation of similar facts in animal physiology. It is very desirable, however, that this study of the vegetable should succeed and not precede that of the domestic animals in the teaching of boys and girls.
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