. Nature and development of plants. Botany. DEVELOPMENT OF PLANTS 209 cell wall which later ruptures and sets them free (Fig. 124, B). The female gametes are without cilia and as they float away in the water they appear to attract the male gametes which swarm about them and finally fertilization is effected by one of the male gametes working down to the nucleus of the female and fusing with it (Fig. 124, C). In an allied form not only is an attractive substance formed in the female gamete, but probably a repellent. Fig. 124. Female gametangia: A, greatly enlarged view of one of the oogonia sho
. Nature and development of plants. Botany. DEVELOPMENT OF PLANTS 209 cell wall which later ruptures and sets them free (Fig. 124, B). The female gametes are without cilia and as they float away in the water they appear to attract the male gametes which swarm about them and finally fertilization is effected by one of the male gametes working down to the nucleus of the female and fusing with it (Fig. 124, C). In an allied form not only is an attractive substance formed in the female gamete, but probably a repellent. Fig. 124. Female gametangia: A, greatly enlarged view of one of the oogonia shown in Fig. 122, C. The oogonium is dividing and forming the female gametes; p, paraphyses. B,- the female gametes discharged but still retained in the inner wall of the oogonium. C, greatly enlarged view of a gamete which is surrounded by male gametes, some of which are seen as dark bodies penetrating the cytoplasm of the female gamete. D, early stage in the germination of the gametospore. See later stage, Fig. 121, C.—^After Thuret. one after fertilization is effected, for Farmer observed that the male cells swarm about the female cells for a time and then sud- denly swim away "like a flock of frightened ; As soon as fertilization has been effected, the gametospores become invested with a cell wall and attached to the rocks. Cell division now proceeds rapidly and soon establishes the characteristic thallus of the plant (Figs. 124, D; 121, C). Fucus is a very prolific plant 14. 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 Curtis, Carlton Clarence, 1864-1945. New York, H. Holt
Size: 1605px × 1556px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, bookpublisher, booksubjectbotany
