. Nature and development of plants. Botany. 358 MALE GAMETOPHYTE OF ZAMIA be compared with that of Selaginella (Fig. 247, A); the cell (g) representing the small cell, and the cell (a) corresponding to the large antheridial cell of the gametophyte of Selaginella (Fig. 243, i), while the cell (t) called the tube cell, represents a new depar- ture in the evolution of the male gametophyte. The tube cell. Fig. 247. Male gametophyte of Zamia: A, stage of germination of the microspore attained in the sporangium. See text for explanation of figures. B, formation of tube for absorbing of food from meg
. Nature and development of plants. Botany. 358 MALE GAMETOPHYTE OF ZAMIA be compared with that of Selaginella (Fig. 247, A); the cell (g) representing the small cell, and the cell (a) corresponding to the large antheridial cell of the gametophyte of Selaginella (Fig. 243, i), while the cell (t) called the tube cell, represents a new depar- ture in the evolution of the male gametophyte. The tube cell. Fig. 247. Male gametophyte of Zamia: A, stage of germination of the microspore attained in the sporangium. See text for explanation of figures. B, formation of tube for absorbing of food from megasporangium. C, spore end of gametophyte showing the antheridial cell dividing into a body cell, 6, and a single wall cell, w. D, the body cell has divided, forming two cells which become the male gametes. E, spore end of male gametophyte, show- ing the spirally ciliated gametes.—After Webber. grows out into the tissues of the megasporangium, forming a tubular structure, often branching extensively, and absorbs food for the nourishment of the antheridial cell (Fig. 247, B). This latter cell finally divides, forming a rudimentary antheridium con- sisting of but a single wall cell (w) and a body cell (&). The body. 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
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Keywords: ., bookcentury1900, bookdecade1910, bookpublisher, booksubjectbotany
