598 Prof. H. E. Armstrong and Dr. E. F. Armstrong. [Apr. 29, 



But such agents often exercise an anresthetic and even a lethal effect if their 

 action be prolonged — how is this to be accounted for ? In plants, anaesthesia 

 is shown by the cessation of protoplasmic movements — as in the well-known 

 case of Eloclca canadensis, for example. Attention has been drawn by Farmer 

 and Waller* to the effect which carbon dioxide, ether and chloroform have in 

 checking the protoplasmic currents in this plant in comparison with that 

 produced by them in depriving muscle of the power of responding to stimula- 

 tion. In neither case is the inhibitive effect permanent, recovery following 

 the removal of the vapour. 



We would venture to attribute the movements in Elodea to molecular 

 interactions consequent on the assimilative activity of the protoplasmic 

 complex. In an assimilating vegetable cell, tire osmotic tension must be 

 subject to continual change as molecules of carbon dioxide and other simple 

 materials are removed from solution and are raised to various levels of 

 complexity; as such molecules disappear from solution, others diffuse in 

 from outside sources. The more complex molecules that come into being 

 are in part rendered more or less nearly inoperative by incorporation in the 

 protoplasmic complex but some are highly attractive of water, as are 

 also the products of the down grade changes which occur concurrently witli the 

 synthetic operations. The consequence of all these changes is that the solvent 

 water in the cells is in the constant state of flux pictured in the expression 

 (HzO)! ^a^H20 ; the movements of the protoplasm are presumably con- 

 ditioned by the numerous exchanges which take place between the hydrolated 

 colloid surfaces and the solution. The stoppage of movcunents by substances 

 which act as anaesthetics may be ascribed to the increase of osmotic tension 

 which tliese condition in the solution and the consequent balance of the 

 attraction previously existing between the protoplasmic mass (the spongio- 

 plasm) and the liquid. 



In the case of muscular tissue, far reaching effects must be produced by 

 the translocation of water consequent on the passage of diffusible substances 

 into the various cellular elements ; at first this should stimulate change, 

 much as in the case of the laurel leaf, by promoting enzymic interactions ; 

 after a time, as the amount of material capable of undergoing such changes 

 became reduced, however, the excitant would lose its influence aiul osmotic 

 cquilibriMiii would soon be restored. The noi^nial activity of muscle may be 

 regarded as at least largely determined by and consequent upon the move- 

 ment of water within its substance. One, if not the chief, effect of electrical 

 stimulation on unexhausted muscle presumal)Iy is to cause the liberation 

 here and there of prodiuas of electrolysis which serve to direct an iuHux of 



* 'Koy. Soc. I'roc.,' 1898, vol. (>;{, ]). 21 3. 



