. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. PLECTOMYCETES [CH. the usual row of three to five cells is formed. The penultimate cell regularly contains more than one nucleus; the rest, as a rule, are uninucleate. Just after fertilization the sheath begins to grow up (fig. 44 b), springing in this case from the stalk cell of the antheridium, as well as from that of the oogonium, and developing into the three layers described above. The ascogenous hyphae arise as lateral branches from the septate oogonium (fig. 44 <r), all or most being derived from the penultimate cell about which
. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. PLECTOMYCETES [CH. the usual row of three to five cells is formed. The penultimate cell regularly contains more than one nucleus; the rest, as a rule, are uninucleate. Just after fertilization the sheath begins to grow up (fig. 44 b), springing in this case from the stalk cell of the antheridium, as well as from that of the oogonium, and developing into the three layers described above. The ascogenous hyphae arise as lateral branches from the septate oogonium (fig. 44 <r), all or most being derived from the penultimate cell about which they are crowded and intertwined. They are at first multi- nucleate, and, as development proceeds, push up vertically within the peri- thecium (fig. 45); septation then takes place. The asci, of which there are several in each perithecium, arise as lateral outgrowths from the intercalary cells, or are formed directly from the terminal cells of the ascogenous hyphae. Each young ascus contains two nuclei, but the remaining cells are almost without exception uninucleate. Fusion takes place in the ascus (fig. 46) and is followed by three nuclear divisions; as a rule only two spores are Fig. 45. Phyllactinia CoryUa (Pers.) Karst.; peri- thecium containing uninucleate asci; after 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 Gwynne-Vaughan, Helen Charlotte Isabella (Fraser) Dame, 1879-. Cambridge [Eng] University Press
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectfungi, bookyear1922
