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The servants of these goddesses were priestesses, or at a later date men dressed as women. At first the gods, in so far as they had any existence, appear in the form of temporary lovers of the goddesses; they are very plainly the transitory male element needful for fertilisation, and then destined to disappear. We find very early the brother as the husband and dependent of the Mother-goddess.
That there is a close connection between the two events seems undoubted; that they are in relation of cause and effect seems likely. It is quite evident that an artificial stimulus can in certain cases set up segmentation, but never can it cause the fertilisation of the ovum.
Girou de Buzareingues crossed three varieties of gourd, which like the maize has separated sexes, and he asserts that their mutual fertilisation is by so much the less easy as their differences are greater. How far these experiments may be trusted, I know not; but the forms experimentised on, are ranked by Sagaret, who mainly founds his classification by the test of infertility, as varieties.
There have, however, been important experiments on the subject of the development of eggs without fertilisation in recent years, prior to these discoveries as to the frog's egg. The eggs are so transparent and so easily kept alive in jars of sea-water that there is no difficulty in watching under the microscope the penetration of the egg by a sperm, and the fusion and other changes in the nuclei.
But fertilisation is more sure and effective if the pollen comes from a different individual if there is "cross fertilisation." This may be accomplished by the simple agency of the wind blowing the pollen broadcast, but it is done much better by insects, which brush against the stamens, and carry grains of the pollen to the next flower they visit.
The reproductive cells also undergo division and increase in number, and when they separate from the new individual and unite in fertilisation they still possess all the determinants of the fertilised ovum from which they are descended. Heredity thus continues from gamete to gamete, not from zygote to soma, and then from soma to gamete.
On fertilisation two kinds of zygotes are formed, female-producing eggs with 2N chromosomes, and male-producing eggs with 2N-1 or 2N-2 chromosomes.
The further development of his views on the importance of cross fertilisation appears to have taken place between this time and 1857, when he published his first papers on the fertilisation of flowers in the "Gardener's Chronicle."
On the contrary, plants with very little special adaptation to any particular insect, like the water-lilies and the poppies, are obliged to flaunt forth in very brilliant hues, and to run to very large sizes in order to attract the attention of a great number of visitors, one or other of whom may casually fertilise them; while plants with very special adaptations, like the sage and mint group, or the little English orchids, are so cunningly arranged that they can't fail of fertilisation at the very first visit, which of course enables them to a great extent to dispense with the aid of big or brilliant petals.
Ferguson, Mr., on the courtship of fowls. Fertilisation, phenomena of, in plants; in the lower animals. Fertility lessened under changed conditions. Fevers, immunity of Negroes and Mulattoes from. Fiber zibethicus, protective colouring of it. Fick, H., effect of conscription for military service. Fidelity, in the elephant; of savages to one another; importance of.
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