Growth and tropic movements of plants / by Sir Jagadis Chunder Bose.

  • Jagadish Chandra Bose
Date:
1929
Catalogue details

Licence: In copyright

Credit: Growth and tropic movements of plants / by Sir Jagadis Chunder Bose. Source: Wellcome Collection.

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    was increased to 5 seconds. The middle record N (fig. 7) was taken at the temperature of the room. The temperature was next lowered by a few degrees and the record C shows the result. Tinally, the record H was obtained when the temperature was raised a few degrees above that of the room. It will be seen that under the action of cold the space between successive dots became shortened, ex- hibiting a diminution in the rate of growth. Heat, on the Fig. 7. Fig. 8. Fig. 7. Effect of temperature recorded with stationary plate. n, normal rate ; c, retarded rate under cold ; h, enhanced rate under heat. (Kysoor.) Fig. 8. Record of a single growth-pulse of Zephyranthes. (Magnification 10,000 times.) other hand, caused a widening of the interval between successive dots, thus demonstrating enhancement of the rate. Calculating from the data supplied by the record : The absolute value of normal rate is 0*457 g per sec. Diminished rate under cold . . o-ioiu ,, ,, Enhanced rate under heat . . °'737 b >> Experiment 5- Pulsation in growth.—As a further example of the capability of the Crescograph, I give the