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LONDON. The Royal Society, November 10.—Prof. C. S. Sherrington, president, in the chair.—A. J. Wilmott: Experimental researches on vegetable assimilation and respiration. XIV.—Assimilation by submerged water plants in dilute solutions of bicarbonates and of acids: an improved bubble-counting technique. The increase of “bubble rate” of carbon dioxide liberated from the cut stem of a water-plant when free acid is added to the water covering the stem is due to the effect of the acid upon carbonates present. No increase is found when soft water is used. In “bubble rate” experiments, solutions of carbonic acid and of sodium bicarbonate of known strength behave similarly.—E. G. Young: The coagulation of protein by sunlight.—E. G. Young: The optical rotatory power of crystalline ovalbumin and serum albumin.—A. R. Ling and D. R. Nanji: The longevity of certain species of yeast. Yeast cultures prepared in 1887 by the late Prof. Hansen were found to be still living. The form in which they have retained their vitality is not determined. A. apiculatus hibernates in the soil; since the yeast with which Hansen worked does not form endospores it may have been preserved as resting cells.—F. Kidd, C. West, and G.E. Briggs: A quantitative analysis of the growth of Helianthus annuus. Part I—The respiration of the plant and of its parts throughout the life-cycle. The respiration of the plant was investigated (1) for calculating loss in dry-weight, due to respiration under field conditions, and, with the increase in dry-weight due chiefly to assimilation, to construct a “balance sheet” for the plant; (2) to determine effect of age of the plant (internal factor) upon its respiration, which was measured under standard conditions at weekly intervals throughout the life cycle. The amount of carbon dioxide (mgs.) per gm. dry-weight per hour produced by the respiring tissue under standard conditions is called the “respiratory index,” which is a close measure of the “effective amount of respiring cell-matter.” The relation between respiration and temperature (0–25°.C.) was also determined. The “respiratory index” of the whole plant and of individual organs decreases throughout the life-cycle, in the case of the whole plant from 3 to about 0.3. Its fall follows closely the fall in “relative growth rate.”—G. S. Currey: The colouring matter of red roses.
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Societies and Academies. Nature 108, 388–391 (1921). https://doi.org/10.1038/108388a0
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DOI: https://doi.org/10.1038/108388a0