170 LIFE AND WORK OF SIR JAGADIS C. BOSE 



essential physiological point of view, and the physio- 

 logists who had so far lost it. For they were thinking 

 but anatomically that, since their sections had not revealed 

 any striking nervous tissue like that of animals, nothing 

 nervous could be there : whereas, had they held to 

 their own fundamental experience and conception of the 

 physiology of living protoplasm that it presents respira- 

 tion, though without gills ; digestion, though without 

 stomach ; and movement, though without muscles they 

 would have realised the possibility of conduction of excita- 

 tion without a highly developed nervous system. Moreover, 

 intercellular continuity between vegetable cells has now long 

 been known to microscopists ; and this not only in many 

 cellular tissues, but more distinctly in and throughout 

 certain elements of nbro-vascular bundles, in which there 

 is more or less protoplasmic continuity, which is essential 

 for conduction of excitation, and to these it was not un- 

 reasonable to suspect conducting powers. Just as Lavoisier 

 at once grasped the universality of the principle of the 

 respiration process in living beings, and boldly correlated 

 this with the process of oxidation, from slow rusting to 

 active combustion, on the inorganic plane, so Bose, with 

 similar range of comparison, has made and verified the 

 analogous step with regard to irritability in the plant and 

 transmission of excitation to a distance, thus extending 

 our conceptions of the highly evolved muscle and nerve 

 of animals to the simpler, yet fully similar contractile cells 

 and conducting tissues in plants. 



Bose's researches on conduction of excitation in plants 

 have now received full acceptance, and his conclusions are 

 published in the ' Philosophical Transactions ' of the Royal 

 Society. 1 In this paper Bose was able to show that the 

 transmission is not hydro-mechanical, as has been previously 

 supposed, for the impulse was shown to be initiated in the 

 complete absence of any mechanical disturbance. All the 



1 ' On an Automatic Method for the Investigation of Velocity of Trans- 

 mission of Excitation in Mimosa,' Philosophical Transactions, vol. 204. 



