. The power of movement in plants . Plants; Botany. Ciur. XI. TRANSMITTED EFFECTS : VICIA. 5?1 the whole growing portion; and after the 24 h. tliis part had a mean length of 37 mm., so that it had increased to more than '6k times its original length; but it should be remembered that these beans had been exposed to a rather high tempeiature. Nineteen young radicles with cauterised tips were extended at different times horizontally over water. In everj trial an equal number of control specimens were observed. In the first trial, the tips of three radicles were lightly touched with the caustic fo
. The power of movement in plants . Plants; Botany. Ciur. XI. TRANSMITTED EFFECTS : VICIA. 5?1 the whole growing portion; and after the 24 h. tliis part had a mean length of 37 mm., so that it had increased to more than '6k times its original length; but it should be remembered that these beans had been exposed to a rather high tempeiature. Nineteen young radicles with cauterised tips were extended at different times horizontally over water. In everj trial an equal number of control specimens were observed. In the first trial, the tips of three radicles were lightly touched with the caustic for 6 or 7 seconds, which was a longer application than usual. A iter 23 h. 30 m. (temp. 55°-56° F.) these three radicles^. Yicia fdba, state of radicles which had been horizontally for 23 h. 30 m.: A, B, C, tips touched with caustic ; D, E, F, tips uncaute- rised. Lengths of radicles reduced to one-half scale, but by an accident the beans themselves not reduced in the same degree. A, B,0 (Fig. 196), were still horizontal, whilst tlie three control specimens had become within 8 h. slightly geolropic, and strongly so (D, E, F) in 23 h. 30 m. A dot had been made on all six radicles at 10 mm. from their tips, when first placed horizontally. After the 23 h. 30 m. this terminal part, originally 10 mm. in length, had increased in the cauterised specimens to a mean length of 17'3 mm., and to 15-7 mm. in the control radicles, as shown in the figures by the unbroken transverse line; the dotted line being at 10 mm. from the apex. The con- trol or Tincauterised radicles, therefore, had actually grown less. 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, Charles, 1809-1882; Darwin, Francis, Sir, 1848-1925. New York : D. Appleton
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Keywords: ., bookcentury1800, booksubjectbotany, booksubjectplants, bookyear18
