. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. MUSCINE/E—HEPA TICM—MARCHANTIALLS 63 are larger and more definite than those of the latter. At this stage the cells begin to separate by a partial deliquescence of their cell walls, and when stained with Bismarck-brown these mucilaginous walls colour very deeply, and the cells are very distinct in sections so treated. They finally separate com- pletely, and the much-enlarged globular capsule now contains a mass of isolated cells of two kinds, globular sporogenous cells and elongated elaters. T
. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. MUSCINE/E—HEPA TICM—MARCHANTIALLS 63 are larger and more definite than those of the latter. At this stage the cells begin to separate by a partial deliquescence of their cell walls, and when stained with Bismarck-brown these mucilaginous walls colour very deeply, and the cells are very distinct in sections so treated. They finally separate com- pletely, and the much-enlarged globular capsule now contains a mass of isolated cells of two kinds, globular sporogenous cells and elongated elaters. The former now divide into four spores, but before the nucleus divides the division of the spores is indicated by ridges which project inward and divide the cavity of the mother cell much as in the Jungermanniacese. With the first divisions in the embryo the venter of the. Fig. 25.—Fimhriaria Californica. A, Young, B, older embryo in median section. A, X300; B, Xioo; C, upper part of a sporogonium, after the differentiation of the archesporium, X200. archegonium, which before was only one cell thick, divides by a series of periclinal walls into two layers of cells, which later undergo further divisions, so that the calyptra surrounding the older capsule may consist of four or more layers of cells. The neck of the archegonium remains unchanged, but the tissue of the thallus below the archegonium grows actively, and sur- rounds the globular foot, which has grown down into the thallus for some distance, and only the capsule remains within the calyptra. This large growth of the foot is at the expense of the surrounding cells of the thallus, which are destroyed by its. 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 Campbell, Douglas Houghton, 1859-1953. New York, The Macmillan Company;
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Keywords: ., bookauthorcampbelldouglashought, bookcentury1900, bookdecade1910
