. A manual of structural botany; an introductory textbook for students of science and pharmacy. Plant morphology. 100 POLLINATION AND FERTILIZATION The Male Gametophyte.—A body of this kind, proceeding from the germination of a matured spore, is properly to be regarded, Hke its female homologue, as a plant body. It is to be noted, in passing, that it can be equally well produced by germination upon other surfaces which present the proper Fig. 277. Diagram illustrating structure of ovule: s, synergidae; u, oGsphere; sek, nucleus; e, embryo-sac; g, antipodal cells. 278. Diagram illu
. A manual of structural botany; an introductory textbook for students of science and pharmacy. Plant morphology. 100 POLLINATION AND FERTILIZATION The Male Gametophyte.—A body of this kind, proceeding from the germination of a matured spore, is properly to be regarded, Hke its female homologue, as a plant body. It is to be noted, in passing, that it can be equally well produced by germination upon other surfaces which present the proper Fig. 277. Diagram illustrating structure of ovule: s, synergidae; u, oGsphere; sek, nucleus; e, embryo-sac; g, antipodal cells. 278. Diagram illustrating fertilization: a, pollen-grains on stigma; 6, pollen-tubes penetrating stigma and style and entering ovarian cavity, one of them entering the foramen of the ovule at c. Following the same course of reasoning as in the case of the female gametophyte, we see that this pollen-tube is the male gametophyte. Its structure is not, or apparently not, even so highly developed as in the case of the other. The Male Cell.—At its lower end are one or more little bodies which constitute the male element and which are to fertilize the oosphere which we have already observed within the embryo-sac. This fertil- izing element is the Male Cell, or Antherozoid. In some of the lowest of the flowering plants, and in most of the Cryptogams, this male cell is highly organized, with a specially formed body, is capable of locomotion, and possesses peculiar powers of nutrition. It is comparable with the spermatozoon of animals. The Descent of the Pollen-tube.—The male cell or antherozoid is quite as incapable of reproducing by itself as is the oosphere, and its sole function is to act upon the latter, fecundating it. This is accomplished. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Rusby, Henry Hurd, 1855-. Philadel
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