. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. I: TELEUTOSPORES i- much thicker a1 the apex than olsouhere ( Fig. |:J). While tin' spores are standing in a densely crowded sinus, the apex is the part most exposed to tin \\ tlicivti)!'.- mosl needing protection. There is a thin endospore t" each cell: the contents aiv granular and at first oily : there is a largo and conspicuous nucleus in the centre of each. This nucleus, in its resting stage, is almost homogeneous except for its nucleolus, and was mistaken by the older obser
. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. I: TELEUTOSPORES i- much thicker a1 the apex than olsouhere ( Fig. |:J). While tin' spores are standing in a densely crowded sinus, the apex is the part most exposed to tin \\ tlicivti)!'.- mosl needing protection. There is a thin endospore t" each cell: the contents aiv granular and at first oily : there is a largo and conspicuous nucleus in the centre of each. This nucleus, in its resting stage, is almost homogeneous except for its nucleolus, and was mistaken by the older observers for a " vacuole" Since the mycelium from which the teleuto- spores, as well as the uredospores, were formed contains paired nuclei, the cells of the teleuto- spore were at first in the same condition. When its wall, however, begins to thicken, when it is becoming mature, the conjugate nuclei unite, and form one large fusion- nucleus (Fig. 14). The two fusing nuclei, after the v< i\ Fig. 13. Teleuto- spore of /'. Caricis. x Fig. 14. Formation of teleutospores of P. Falcariae (after Dittschlag); a, the spore-bearing hypha; b, the same divided into pedicel and spore-cell; c, the spore divided into two cells; d, a young teleuto- spore ; e, the same after the fusion of the nuclei, x about 800. numerous conjugate divisions during the long period of growth from the formation of the fusion-cell of the secidium, would be related, as it were, like very distant cousins, especially since the nuclear divisions during this period, though indirect, appear to show a very simplified form of mitosis, tending rather to be of the nature of amitosis. The fusion, as already intimated, is not to be considered as the act of fertilisation, but merely as a necessary preliminary to 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
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Keywords: ., bookcentury1900, bookdecade1910, bookpublishercambr, bookyear1913
