FUNCTION IN PLANT LIFE 5 



filled with fluids which conduct electricity and are decom- 

 posed by currents. Such being the case, it can scarcely 

 be otherwise than that the electrical tensions between the 

 atmosphere and the earth become equalised through the 

 plant itself. Whether this acts favourably on the processes 

 of vegetation, however, has not been scientifically in- 

 vestigated, since what has been done here and there in the 

 way of experiments in this sense can scarcely lay claim to 

 serious notice." 



Strasburger with whom must be associated Drs. 

 Schenck, Noll, and Karsten has nothing to say upon the 

 subject, and I think it may reasonably be assumed that 

 our knowledge of vegetable electro-physiology is summed 

 up in the extracts I have given. 



The analogies, however, which exist in animal and 

 vegetable physiology, especially in the lower forms of 

 life, are sufficiently full of interest to stimulate further 

 research work. That locomotion and sensitiveness are 

 common to low plants as well as to low animals, that 

 marked similarity exists between the animal and the 

 vegetable cell, and that in the matters of the presence or 

 absence of cellulose and the nature of the food required by 

 both organisms there does not appear to be any absolute 

 point of distinction, seemed to me to invite investigation 

 and encouraged me to undertake it. The theory of 

 evolution, enunciated in its present form by Darwin and 

 by Wallace, regards all forms of life as having a common 

 descent, a true blood relationship, whence arises the 

 impossibility of drawing hard and fast lines of separation ; 

 and my own results are in perfect harmony with this 

 well-established conclusion. 



We know, or at all events it can be demonstrated, that 

 man is a self-contained neuro-electrically controlled 

 machine, dependent for the due performance of his func- 

 tions upon a constant supply of nerve-energy at a low 



