. Morphology of gymnosperms. Gymnosperms; Plant morphology. CONIFERALES (TAXACEAE) 343 much higher number than among the podocarps. The suggestion of a genetic connection between these two tribes will be considered later. The course of spermatogenesis in the podocarps, from the division of the generative cell just before fertilization, presents no unusual features. In Dacrydium (136) it was observed that the generative. Fig. 398.—Phyllocladus alpina: apex of nucellus broken down by numerous pollen tubes; the top of the endosperm also somewhat disorganized; each archegonium is surrounded by a d
. Morphology of gymnosperms. Gymnosperms; Plant morphology. CONIFERALES (TAXACEAE) 343 much higher number than among the podocarps. The suggestion of a genetic connection between these two tribes will be considered later. The course of spermatogenesis in the podocarps, from the division of the generative cell just before fertilization, presents no unusual features. In Dacrydium (136) it was observed that the generative. Fig. 398.—Phyllocladus alpina: apex of nucellus broken down by numerous pollen tubes; the top of the endosperm also somewhat disorganized; each archegonium is surrounded by a definite jacket; Xi8o.—^After Miss Kjldahl (144). cell divides antichnally, the stalk and body cells being side by side and for some time indistinguishable. Presently one of them enlarges, rounds off, and becomes free, while the nucleus of the other becomes free by the disappearance of its wall or membrane. In the two genera in which the male cells have been observed, the two extremes of varia- tion are represented. In Phyllocladus (174) the body cell divides to form two unequal male cells, only one of which functions (fig. 397);. 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 Coulter, John Merle, 1851-1928; Chamberlain, Charles Joseph, b. 1863; Coulter, John Merle, 1851-1928. Morphology of spermatophytes. Part I. Gymnosperms. Chicago, University of Chicago Press
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