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STUDIES IN GENERAL PHYSIOLOGY 



TABLE XVI 



rays, but not with anode rays. Another possibility may be 

 thought of. The egg and all protoplasm is a system 

 with various phases; we have solid parts (membranes), and 

 liquid parts which are either rich or poor in colloids. It is 

 conceivable that the coefficient of distribution for the posi- 

 tive and negative ions is unequal in the various phases, and 

 that this fact leads to the toxic effects of the negative ions 

 which can be annihilated by the addition of a small number 

 of positive ions holding a double or triple charge. 



I was long inclined to look upon the sodium ions as the 

 toxic ions in a pure sodium-chloride solution, and I have 

 upheld this view in my preliminary communication concern- 

 ing these experiments. What led me to this conclusion was 

 the following experiment: I tested the relative toxicity of H 

 and OH ions for the eggs of Fundulus. As was to be 

 expected, it came to light that the hydrogen and hydroxyl 

 ions differ in their toxicity. In a ? ^ KOH solution the 

 eggs developed and formed embryos, while a T ^ TT HC1 solu- 

 tion killed the eggs almost immediately. The hydrogen 

 ions are therefore at least as much as five times as poisonous 

 as the hydroxyl ions. But I do not believe that we are 

 forced to conclude from this that the poisonous effects of a 



