Nature and development of plants . 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
Nature and development of plants . 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,. Fig. 128. Features in the reproduction of Polysiplwiiia: A, branch ofthe plant bearing clusters of male gametangia, an. B, one of the clustersenlarged, showing the numerous small gametangia. C, branch on whichthe spores derived from the gametospore are enveloped by a sac. Fromone of these bodies, called cystocarps, the spores are escaping. B, C), the terminal cells of which develop as spores (Fig. 127,D). These spores on germinating produce the characteristicred algae, which bear tetraspores. The mode of sexual repro-duction outlined above is complicated in the majority of thered algae, owing to the fusion of the germinating gametospore DEVELOPMENT OF PLANTS 193 with adjacent cells that contain storage foods. In this way, theformation of a larger number of spores is made possible. Fre-quently a sac-like structure, the cystocarp, is developed about thespores owing to the outgrowths of the adjacent cells (Fig. 128,C). The red algae are of considerable economic moss, CJw
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