. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. Ill] ERYSIPHALES 87 lose their contents and are displaced by the developing asci. Later the fusion of the two nuclei in each ascus takes place, and in each eight spores are formed. Dangeard, investigating the development of E. Polygoni and E. Cicho- racearum, notes that in his material the oogonium underwent septation before a row of nuclei was formed, and that cells other than the penultimate contained two or more nuclei. Usually in E. Cichoracearum and sometimes in E. Polygoni the oogonial branch consisted of two cells; this corresponds
. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. Ill] ERYSIPHALES 87 lose their contents and are displaced by the developing asci. Later the fusion of the two nuclei in each ascus takes place, and in each eight spores are formed. Dangeard, investigating the development of E. Polygoni and E. Cicho- racearum, notes that in his material the oogonium underwent septation before a row of nuclei was formed, and that cells other than the penultimate contained two or more nuclei. Usually in E. Cichoracearum and sometimes in E. Polygoni the oogonial branch consisted of two cells; this corresponds with the arrangement in the antheridial branch, which is regularly bicellular. In both cases the lower cell is to be regarded as a stalk. In regard to the occurrence of fertilization Dangeard's conclusions correspond with those which he reached in relation to Sphaerotheca. Phyllactinia Corylea infects the leaves of deciduous trees and shrubs in- cluding ash, oak, beech, hazel and hornbeam. The sexual organs arise (Harper 1905), as in other mildews, where two hyphae intersect. They become closely applied to each other, and, as the oogonium grows more quickly than the antheridial branch, it becomes some- what twisted around the latter. The subsequent history is very like that of Sphaerotheca or Erysiphe. A uninucleate antheridium is cut off, the male nucleus enters the female organ (fig. 44a), nuclear fusion takes place, the. 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
