. Practical physiology of plants. Plant physiology; 1894. 160 DECAPITATED ROOTS. [CH. VII (205) Decapitation prevents the perception of the stimulus. Place 10 beans horizontally in damp sawdust for 1^ hours; the tips (1^ mm.) are now amputated and the roots embedded vertically in damp sawdust. After 12 hours the roots, or most of them, will be found to be curved laterally towards,the side which was downwards during the period (IJ hr.) during which they were kept horizontal. This shows that amputation does not interfere with the carrying out of an induced curvature, so that the absence of geotr
. Practical physiology of plants. Plant physiology; 1894. 160 DECAPITATED ROOTS. [CH. VII (205) Decapitation prevents the perception of the stimulus. Place 10 beans horizontally in damp sawdust for 1^ hours; the tips (1^ mm.) are now amputated and the roots embedded vertically in damp sawdust. After 12 hours the roots, or most of them, will be found to be curved laterally towards,the side which was downwards during the period (IJ hr.) during which they were kept horizontal. This shows that amputation does not interfere with the carrying out of an induced curvature, so that the absence of geotropism in exp. 204 must be due to a disturbance of the capability of being stimulated'. (206) Recovery from the effect of amputation. If the roots in exp. 205 are allowed to remain undisturbed for 3 or 4 days, the growing point is regenerated and the roots recover the complete power of geotropic curvature. They will grow into an S-like form, because before the growing point is regene- rated they continue growing horizon- tally or obliquely in the direction impressed on them by the geotropic curvature induced before amputation. When the power of reacting to the ' Neither this experiment, nor the others given in the Paaer of Movement, "prove that the tip alone is sensitive to gravitation, but Pfeffer's brilliant researches, described before Section D of the British Association in August 1894 demonstrate conclusively that this is the 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 Darwin, Francis, Sir, 1848-1925; Acton, Edward Hamilton, d. 1895; Lindley, Nathaniel Lindley, Baron, 1828-1921. sgn. Cambridge, University Press
Size: 1063px × 2352px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectplantph, bookyear1894
