The nervous mechanism of plants / by Sir Jagadis Chunder Bose.

  • Bose, Jagadis Chandra, 1858-1937.
Date:
1926
Catalogue details

Licence: In copyright

Credit: The nervous mechanism of plants / by Sir Jagadis Chunder Bose. Source: Wellcome Collection.

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    carrying the experiment through the usual cycle of opera- tions, it was found that the kathode excited at make and not at break. The effect of the anode, on the other hand, was different; it excited at break and not at make. The automatic record by the plant is given in Fig. 4. The normal signal-line below indicates no current ; the up-line, kathode-make; return to horizontal, kathode- break ; down-line, anode-make ; and return to the hori- zontal represents anode-break. It will be noted that under 8 volts, excitation takes place only at kathode-make. Under 12 volts there is a stronger response at kathode - make and none at kathode- break; no excitation was produced at anode-make, but it occurred at anode- break. The universality of these characteristic polar excitations is Fig. 4. Under 8 volts excitation at kathode- ... . make Km; under 12 volts excitation at proved by the results kathode-make and anode-break Ab. of experiments which I carried out with the sensitive organs of various other plants, such as the leaflets of Mimosa, of Biophytum, of Neptunia oleracea, of Averrhoa Carambola and of Averrhoa Bilimbi. The effective inten- sity of the current depends on the excitability of the particular specimen, a vigorous specimen being excited by a feebler current. It also depends on the relative excit- ability of different motor organs, the pulvinules of the leaflets being, in general, more sensitive than the main pulvinus. As an example of the response of the leaflets, I describe an experiment with Biophytum sensitivum, employing the Bipolar method. The two electrodes were applied at two points on the petiole which carries numerous pairs of motile leaflets.