. The Bible and science. Fig. 26.—Vertical section of flower of hypericum, showing sepals, petals, stamens,ovary and styles. The formation of the male element begins as alittle cellular projection. The cells composing thismultiply, the mass grows larger, and then begins toshow signs of differentiation. In its body larger cellsappear, which form separate clusters, each surroundedby smaller cells, which form a distinct covering for these large cells the pollen is developed. The ovule, or female element, likewise begins as asmall cellular projection, the cells of which multiplyuntil it
. The Bible and science. Fig. 26.—Vertical section of flower of hypericum, showing sepals, petals, stamens,ovary and styles. The formation of the male element begins as alittle cellular projection. The cells composing thismultiply, the mass grows larger, and then begins toshow signs of differentiation. In its body larger cellsappear, which form separate clusters, each surroundedby smaller cells, which form a distinct covering for these large cells the pollen is developed. The ovule, or female element, likewise begins as asmall cellular projection, the cells of which multiplyuntil it becomes an ovoid mass, and then it alsoundergoes differentiation. In its interior, near itsupper end, a cavity begins to form, and to this has 8S OVULE—ANTHER—POLLEN. been given the name of the embryo sac. Usually, also,the cells on the exterior are altered so as to form adouble covering to the body or nucleus of the ovule,leaving, however, at the upper end a small opening. Fig. 29.—Growth of ovule of celandine, n Nucleus, h. First formed covering. c. Second covering, d, Funicle, very greatly enlarged. or foramen, the other end still remaining attachedto the point from which it originally sprung, andthrough it the ovule continues to derive its nutri-ment from the parent plant. The pollen grains, as we
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectnaturalhistory, booky
