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Updated: July 27, 2025
Even in first crosses, the greater or lesser difficulty in effecting a union apparently depends on several distinct causes. There must sometimes be a physical impossibility in the male element reaching the ovule, as would be the case with a plant having a pistil too long for the pollen-tubes to reach the ovarium.
But against this, all our modern authors affirm that the ancients are very erroneous, inasmuch as the testicles in women do not afford seed, but are two eggs, like those of a fowl or other creatures; neither have they any such offices as in men, but are indeed an ovarium, or receptacle for eggs, wherein these eggs are nourished, by the sanguinary vessels dispersed through them; and from hence one or more, as they are fecundated by the man's seed, are conveyed into the womb by the oviducts.
In another nest we found that one white egg, much like that of a pigeon, was laid, and the bird dropped another when captured. She had four besides in the ovarium. The first time that I saw this bird was at Kolobeng, where I had gone to the forest for some timber. Standing by a tree, a native looked behind me and exclaimed, "There is the nest of a korwe."
Thus, as I am inclined to believe, morphological differences, which we consider as important such as the arrangement of the leaves, the divisions of the flower or of the ovarium, the position of the ovules, etc., first appeared in many cases as fluctuating variations, which sooner or later became constant through the nature of the organism and of the surrounding conditions, as well as through the intercrossing of distinct individuals, but not through natural selection; for as these morphological characters do not affect the welfare of the species, any slight deviations in them could not have been governed or accumulated through this latter agency.
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.
As the life of a moth may be indefinitely prolonged whilst its duties are unfulfilled, so the flower of this little mountaineer will remain open through days of fog and sleet, till a mild day facilitates the detachment of the pollen and the fecundation of the ovarium. But here is a plant, or rather flower, more curious than any we have seen.
Hooker informs me that within the same ovarium the upper ovules alone in some cases, and in others the lower ones alone are fertilised; and he suggests that this probably depends on the direction in which the pollen-tubes enter the ovarium.
The time between the deposit of the semen and fecundation varies according to circumstances. If the sperm-cell travels to the ovarium it generally takes from three to five days to make the journey. As Dr. The action of the cilia, under the stimulus of the sperm, seems to be from without, inward.
An organ, serving for two purposes, may become rudimentary or utterly aborted for one, even the more important purpose, and remain perfectly efficient for the other. Thus, in plants, the office of the pistil is to allow the pollen-tubes to reach the ovules within the ovarium.
In the common rue and some other plants, one flower, usually the central or terminal one, opens first, and has five sepals and petals, and five divisions to the ovarium; while all the other flowers on the plant are tetramerous.
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