272 BOTANICAL GAZETTE [OCTOBER 



In general we may know when the solution is properly balanced 

 by comparing its effects with those of pure 1 distilled water. In a 

 properly balanced solution we expect the organism to live approxi- 

 mately as long as in distilled water, and while it will not grow so fast 

 (on account of the osmotic pressure), the ultimate development reached 

 should be comparable with that attained in distilled water. 8 



Why all these effects are so, we are not at present prepared to say 

 in detail. LOEB has gone farther than any other in the explanation 

 of these phenomena, referring them to the effects, of salts and ions on 

 proteids 9 . According to his conception any metal must be poisonous 

 when it alone is present in the solution, for it will enter the proteids 

 and 'drive out other metals in accordance with the law of mass action. 

 This will of course alter the properties of the proteids and so cause 

 disturbances in function. The only way to prevent this is to main- 

 tain a proper balance between the various metals in the solution. 

 It may be pointed out that an analogy exists between the effects 

 described here and various reactions in which proteids are in- 

 volved. Antagonism between Na and Ca, for example, is seen in 

 the clotting of blood, which is hindered by Na and favored by Ca. 



The thing of chief importance is the agreement in behavior of such 

 a great diversity of plants with the fresh-water and marine animals 

 already studied. Thereby is brought to light a new point of similarity 

 between animals and plants which is fundamental in character and 

 which must be taken into consideration in attempting to formulate 

 a theory of living matter. 

 UNIVERSITY OF CALIFORNIA 



7 Water twice distilled from glass, the first third of the distillate being rejected 

 is usually regarded as pure. But such water may be quite poisonous if any part of 

 the apparatus, including stoppers, be new. The longer the apparatus is used the less 

 poisonous the water becomes, until it finally ceases to be toxic. 



8 Higher concentrations excepted. 



9 See references in the first part of this paper, BOT. GAZ. 42: 134. 1906 



