Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 44. Phyllactinia Corylea (Pers.) Karst.; a. fertilization;b. fusion nucleus in oogonium ; c. </. young perithecia ; afterHarper. oogonium elongates and enlarges in diameter and the fusion nucleus first nuclear division is apparently never accompanied by cell wallformation, so that a binucleate stage persists for some time. Finally, however, PLECTOMYCETES [CH. the usual row of three to five cells is formed. The penultimate cell regularlycontains more than one nucleus ; the rest, as a rule, are uninucleate. Just after fertilizat
Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 44. Phyllactinia Corylea (Pers.) Karst.; a. fertilization;b. fusion nucleus in oogonium ; c. </. young perithecia ; afterHarper. oogonium elongates and enlarges in diameter and the fusion nucleus first nuclear division is apparently never accompanied by cell wallformation, so that a binucleate stage persists for some time. Finally, however, PLECTOMYCETES [CH. the usual row of three to five cells is formed. The penultimate cell regularlycontains more than one nucleus ; the rest, as a rule, are uninucleate. Just after fertilization the sheath begins to grow up (fig. 44 o), springingin this case from the stalk cell of the antheridium, as well as from that ofthe oogonium, and developing into the three layers described above. The ascogenous hyphae arise as lateral branches from the septateoogonium (fig. 44 c), all or most being derived from the penultimate cellabout which they are crowded and intertwined. They are at first multi-nucleate, and, as development proceeds, p
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectfungi, bookyear1922
