Nature and development of plants . featurescan be pointed out. Singularly the spores and gametes havelost their motility. Asexual reproduction is extensively broughtabout by spores that are usually formed in fours from a mothercell (Fig. 126) and therefore called tetraspores. These spore-forming mother cells arise singly on the surface or in the tissuesof the plant, or they may be associated in conspicuous spores escape from the mother cell as naked bodies andfinally secrete cell walls and develop into new plants. The sexualmethod of reproduction is the most complicated among all th
Nature and development of plants . featurescan be pointed out. Singularly the spores and gametes havelost their motility. Asexual reproduction is extensively broughtabout by spores that are usually formed in fours from a mothercell (Fig. 126) and therefore called tetraspores. These spore-forming mother cells arise singly on the surface or in the tissuesof the plant, or they may be associated in conspicuous spores escape from the mother cell as naked bodies andfinally secrete cell walls and develop into new plants. The sexualmethod of reproduction is the most complicated among all thealgae, and even in the simplest form is far in advance of anymethod heretofore noted. The female gametangium resemblesa flask with a long neck and is usually developed at the end ofa branch (Fig. 127, A), see Coleocliaetc. The single femalegamete is found at the base of the flask. The male gametes areproduced singly in small cells also at the ends of branches andthey are often closely aggregated in dense clusters (Figs. 127, an;. Fig. 127. Sexual reproduction in Ncmalion: A, tip of branch bearingfemale gametangium, c, and cluster of male gametangia, an, from someof which the motionless male gametes are escaping. B, first division ofthe germinating gametospore, g. C, later stage showing the early forma-tion of the branches from which the spores will be developed. D, sporesforming at the ends of the numerous branches. 192 REPRODUCTION OF THE RED ALGAE 128, A, B). After the discharge of the male gamete, they arecarried by the currents of the water to the long tube of thefemale organ. The wall of the tube at the point of contact isnow absorbed and the male gamete passes down the tube andfuses with the female. The gametospore does not germinateand produce a new plant similar to the one that bore the the other hand, it produces a number of branches (Fig. 127,
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