. Carnegie Institution of Washington publication. mm) J7. Fig. 33.* The next step, therefore, was to add and exclude nodules or nodule products, and so determine the results experimentally. This was done by taking 40 experimental pots containing nitrogen-free soil, holding 30 for checks, and to the other 10 adding 25 cc. of an extract of fertile soil, containing only 1 mg. of nitrogen per pot, all being planted to peas. All passed through a period of nitrogen- hunger, but the plants in the pots inoculated with the soil-extract all regained their green color and grew freely and uniformly. In on
. Carnegie Institution of Washington publication. mm) J7. Fig. 33.* The next step, therefore, was to add and exclude nodules or nodule products, and so determine the results experimentally. This was done by taking 40 experimental pots containing nitrogen-free soil, holding 30 for checks, and to the other 10 adding 25 cc. of an extract of fertile soil, containing only 1 mg. of nitrogen per pot, all being planted to peas. All passed through a period of nitrogen- hunger, but the plants in the pots inoculated with the soil-extract all regained their green color and grew freely and uniformly. In only 2 of the 30 check pots did the plants grow freely. All the rest continued to show nitrogen-hunger, and some became quite yellow. This difference in color and amount of growth was found to be correlated with the presence or absence of root-nodules. *Fig. 33.—Nos. 8 to 11. Stages in development of root-nodules on common garden lupin {Lupinus mutabilis). No. 12. Same in tranverse section as seen under a hand-lens. Same as 12 but in longitudinal section; ap, external parenchyma; ip, internal parenchyma; gb, vascular bundles. Cross-section, x 120. Mature cells of internal parenchyma containing rod-shaped corpuscles, x 320. Cell showing escape of rod-shaped bodies by resorption of membrane, x 320. Mass of bacteria surrounding nucleus which has survived cell membrane, x 620. Isolated bacteria which have become modified and have ceased to be motile, x 620. 14- No. No. No. No. 16. No. 17. No. 18. After Woronine. Reduced 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 Carnegie Institution of Washington. Washington, Carnegie Institution of Washington
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Keywords: ., bookauthorcarnegie, bookcentury1900, bookdecade1910, bookyear1911
