. The essentials of botany. Botany. PETCOPHTTA. 145 pearing like an extension of the hypha, then called the columella {G, a). The protoplasm in the enlarged termi- nal cell (J) divides into a large number of minute masses, each of which surrounds itself with a cell-wall; these little. Fig. 75.—Diagrams showing mode of growth of the spore-case of Mucor mucedo. ^, very young stage ; B, somewhat later; C, spore-case with ripe spores, a in all the figures represents the partition-wall between the last cell of the filament and the spore-case, &. cells are the spores, and the large mother-cell i
. The essentials of botany. Botany. PETCOPHTTA. 145 pearing like an extension of the hypha, then called the columella {G, a). The protoplasm in the enlarged termi- nal cell (J) divides into a large number of minute masses, each of which surrounds itself with a cell-wall; these little. Fig. 75.—Diagrams showing mode of growth of the spore-case of Mucor mucedo. ^, very young stage ; B, somewhat later; C, spore-case with ripe spores, a in all the figures represents the partition-wall between the last cell of the filament and the spore-case, &. cells are the spores, and the large mother-cell is now a spore-case, or sporangium. 258. The spores are set free in different ways: in some cases the wall of the spore-case is entirely absorbed by the time the spores are mature; in other cases only portions of the wall are absorbed, producing fissures of various kinds. The spores germinate readily when on or in a substance capable of nourishing them, by sending out one or two hyphge, which soon branch and give rise to a mycelium. Spores may, if kept dry, retain their vitality for months. 259. Sexual reproduction takes place after the produc- tion of asexual spores. Two hyphse, in the air or within the nutritive medium, come near each other, and send out small branches, which come in contact with each other {a, Fig. 76); these elongate and become club-shaped, and at the same time they become more closely united to each other at their larger extremities (5); a little later a trans- verse partition forms in each at a little distance from their place of union (c); the wall separating the new terminal. 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 Bessey, Charles E. (Charles Edwin), 1845-1915. New York : Holt
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbotany, bookyear1896
