. La morphologie comparative et de la biologie des champignons, bactéries et mycetozoa. Champignons -- la morphologie ; bactéries -- la morphologie. 7- DIVISIOX 1. -La morphologie générale. L'une appartenant à la sixième colonne vertébrale en youngesl la chaîne. Essentiellement les mêmes phénomènes se produisent dans d'autres espèces de l'Uredineae, mais avec des variations considérables de forme dans les différentes espèces1. Les sporophores filiformes où lieu gratuitement dans l'air, un autre- ment organiser mécanique est trouvé qui aide grandement l'effusion et la dispersion de l'abscised les spores. Il ma) être facilement observée dans le Hyphomycetess à Peronospora, par exemple, Ph

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. Comparative morphology and biology of the fungi, mycetozoa and bacteria. Fungi -- Morphology; Bacteria -- Morphology. 7- DIVISIOX 1. -GENERAL MORPHOLOGY. one belonging to the sixth youngesl spine in the chain. Phenomena essentially the same occur in other species of the Uredineae, but with considerable variations in form in the different species1. Where filiform sporophores rise free into the air, a further mechanical arrange- ment is found which greatly assists the shedding and scattering of the abscised spores. It ma) be readily observed in the Hyphomycetess in Peronospora, for example, Phytophthora infestans, and in the gonidiophores of Peziza Fuckeliana, &c. The hyphae of these Fungi are cylindrical in the moist and turgescent state, but collapse when dry and especially when the spores are ripe into a flat ribbon-like form2, and the drier they are the more strongly do they become twisted round their own longitudinal axis. They are so highly hygroscopic that the slightest change in the humidity of the surrounding air, such for instance as may be caused by the breath of the observer, at once produces changes in their turgescence and torsion; the latter give a twirling motion to the extremity of the gonidiophore and the ripe spores are thereby thrown off in every direction. Abjection of acrogenous propagative cells is effected by a mechanism which we shall have to speak of again in section XXI. The cell which is to be abjected, whether spore or spore-mother-cell (for brevity we shall call it spore), is abjointed singly by a cross septum at the apex of a tubular and often comparatively large sporiferous cell, a basidium or a sterigma, which retains its parietal protoplasm still intact after the abjunction of the spore and is still turgescent in consequence of a continued supply of water in increasing quantity. Its membrane is highly extensible and elastic, and continues to stretch as the tension increases with the increased amount of water absorbed. But its co

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