Mast, Samuel Ottmar, 1871- · New York, J. Wiley · leaf 99
ionof one intensity to that of another, or to a change in theaxial position of the organism with reference to the sourceof light. There is no evidence that orientation is due to aconstantly acting directive stimulus in accord with Loebstheory of troplsms. Jennings does not deny that the 84 LIGHT… … Fig. 12. Illustration of the devious path followed by Euglena in becomingoriented when the direction of the light is reversed. From i to 2 the light comesfrom above; at 2 it is reversed. The amount of wandering (a-h) varies in differentcases. After Jennings (igo6, p. 137). Torrey (1907, pp. 317,…
Light -- Physiological effect · Phototropism
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