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If the spike of the hybrid contains dormant paternal marks in one-half of its flowers and in the other half maternal latent qualities, the sugar-corn pollen will combine with one-half of the ovules to give hybrids, and with the other half so as to give pure sugar-grains. Hence we see that it will be possible to count out directly the two groups of ovules on inspecting the ripe and dry spikes.
We had to pass on to the flower, and learn the use of the covering leaves, the gaily coloured crown attracting the insects, the dust-bags holding the pollen, the little ovules each with the germ of a new plantlet, lying hidden in the seed- vessel, waiting for the pollen-grains to grow down to them.
Hind-brain, cerebellum, medulla oblongata. d. Eye. e. Ear. f. First visceral arch. g. Second visceral arch. H. Vertebral columns and muscles in process of development. i. Anterior extremities. K. Posterior extremities. Man is developed from an ovule, about the 125th of an inch in diameter, which differs in no respect from the ovules of other animals.
One can observe the browning and ripening of the stigma after pollen has been deposited by wind, bees or other agencies. When the ovules are fertilized, the forming fruit enlarges regularly unless it meets with misfortune or is crowded out for lack of room and nourishment. In each cell are two ovules; these, if all goes well, will ripen into ten seeds.
Although the plants in these experiments appeared perfectly healthy, and although both the ovules and pollen of the same flower were perfectly good with respect to other species, yet as they were functionally imperfect in their mutual self-action, we must infer that the plants were in an unnatural state.
Still more wonderful is the fact that it is these temporary existences which, in accordance with the general law of life-production, form special "ovules," which we call seeds, each of which has the potentiality for growing up into a great forest tree, which, in its turn, is capable of pushing forth temporary existences in countless directions.
Every stage of evolution is here represented, distributed regularly from bottom to top, from the verge of maturity to the vague outlines of the embryo. The sheath clasps its string of ovules so closely that any inversion of the order is impossible. Besides, an inversion would result in a gross absurdity: the replacing of a riper egg by another in an earlier stage of development.
The mother, without troubling unduly whether there be an excess or a dearth of provisions for her family, has filled the cells as her fancy prompted, or rather according to the number of ripe ovules contained in her ovaries at the time of the laying.
The child, knowing about the fertilization of flowers, can easily be led to see that the fish ova, like the flower ovules, cannot develop without pollen. The anthers containing the pollen are found in the male fish, and look like the ovaries, only they are not so large and their contents are not so firm. They seem filled with a formless substance instead of with little globular eggs.
They are egg-shaped, about an inch in diameter, and furnish the germs or ovules. These germs or ovules are very small, measuring about 1/120 of an inch in diameter. DEVELOPMENT. The ovaries develop with the growth of the female, so that finally at the period of puberty they ripen and liberate an ovum or germ vesicle, which is carried into the uterine cavity of the Fallopian tubes.
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