. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. Fig 179. a. Phragviidium Rubi Pers.; uredosorus, x6oo; after Sappin-Tiouffy; /'. Phragmidium violaceum'; uredosorus, X480; after Blackman. by paraphyses, or in certain genera {Pucciniastrum, Uredinopsis) by a pseudo- peridium. In the young sorus a regular layer of somewhat rectangular basal cells is formed, from which the uredospore mother-cells arise. In Coleo- sporium, in Chrysomyxa, and in the secondary caeomata of Phragmidium subcorticiuin, they are produced in vertical rows like the typical aecidiospore mother-cells and divide
. Fungi, ascomycetes, ustilaginales, uredinales. Fungi. Fig 179. a. Phragviidium Rubi Pers.; uredosorus, x6oo; after Sappin-Tiouffy; /'. Phragmidium violaceum'; uredosorus, X480; after Blackman. by paraphyses, or in certain genera {Pucciniastrum, Uredinopsis) by a pseudo- peridium. In the young sorus a regular layer of somewhat rectangular basal cells is formed, from which the uredospore mother-cells arise. In Coleo- sporium, in Chrysomyxa, and in the secondary caeomata of Phragmidium subcorticiuin, they are produced in vertical rows like the typical aecidiospore mother-cells and divide to form uredospores and intercalary cells, but, in the large majority of cases, they appear as a succession of buds from different parts of the basal cell. Each bud elongates, its nuclei undergo conjugate division, a stalk is cut off which grows in length but remains narrow, while the uredospore enlarges considerably, its contents acquire an orange or yellow colour, and its wall is variously roughened in most species by minute projections on the surface. Two or more germ-pores are usually present and the uredospore, like the cells which give rise to it, is invariably binucleate; it produces a binucleate mycelium on which teleutospores or further crops of uredospores are formed. Certain {Puccinia vexans,etc.),occurnng under very dry 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
