42 CELLULAR 



far the cell may become so permeable that no 

 recovery is possible, but up to a certain point 

 increase in permeability would increase the rate 

 of recovery from plasmolysis if exosmosis were 

 not greater than endosmosis. From this stand- 

 point we might expect the recovery in sodium 

 chloride to be more rapid than in a balanced 

 solution of sodium and calcium chlorides (or 

 in sea water) since alterations in permeability 

 would be more rapid in sodium chloride. This 

 seems to be the case. When recovery occurs in 

 balanced solutions it is possible that it is also due 

 to alterations in permeability, since it is well 

 known that hypertonic balanced solutions may 

 cause injury. 



If ions are unable to penetrate normal proto- 

 plasm how are we to regard the experiments 

 which indicate that marine plants bathed in sea 

 water allow ions to enter the protoplasm and 

 thus conduct the electric current under condi- 

 tions which seem to ensure that the cells are in a 

 normal state? 



In the first place it is possible that if the cell 

 normally opposes a high resistance to the 



