1918] Waynick: Antagonism and Cell Permeability l.">7 



salts. Probably the work of Abbott, Conner and Smalley 88 is of more 

 direct interest here. These investigators found aluminum nitrate to 

 be toxic to corn seedlings in the presence of nutrient solutions. 

 E. Kratzmann 39 has reported stimulation due to the presence of small 

 amounts of aluminum salts. Miyake 40 concludes further that the 

 effects observed with aluminum chloride cannot be attributed to the 

 hydrogen ion resulting from the dissociation of the salt. 



Aluminum chloride was found to be toxic in every concent ration 

 used in the present work. The effect of the presence of calcium 

 chloride in a concentration of .20 M. was to decrease growth still fur- 

 ther, indicating that its toxic effect, as reflected in growth, was but 

 additive to that of aluminum chloride. With magnesium chloride 

 present in equivalent concentration as the calcium chloride, there is a 

 marked antagonism at a concentration of .000066 M. of aluminum 

 chloride with .20 M. magnesium chloride. The increase in dry weight 

 was 100 per cent greater than in an equivalent concentration of 

 aluminum chloride alone and 300 per cent greater than with mag- 

 nesium chloride in the concentration given. This culture has been 

 referred to especially since it furnishes a striking example of antag- 

 onism between bivalent and trivalent salts, botli of which are highly 

 toxic when used alone. The chloride ion was a constant as far as this 

 and the preceding series are concerned, the only difference between 

 the two cases being the use of calcium chloride in one and magnesium 

 chloride in the other. It seems logical to conclude that the action is 

 specific as regards the magnesium and aluminum ions. Whatever 

 the nature of this action may be, it is certainly not shown between 

 calcium and aluminum ions. 



The same general relationships are brought out between ferric 

 chloride and calcium and aluminum chlorides. Ferric chloride did 

 not prove toxic in the concentrations used, growth differing but little 

 from that of the control. When calcium chloride was present in a 

 concentration of .20 M. throughout the series, growth was half or Less 

 than half that recorded when ferric chloride alone was present. 

 Magnesium chloride in equivalent concentrations, as the calcium 

 chloride above, affected growth but little. In other words, magnesium 

 chloride did not prove toxic in the presence of certain concentrations 

 of ferric chloride. The relations between the four salts may lie briefly 

 summarized as follows: There is no antagonism shown between alumi- 



38lnd. Exp Sta. Bull. 170 (1913), p. 329. 



s»Chem. 7Ag., vol. 38 (1914), p. 1040. 



*» .lour. Biol. Chem., vol. 25 (1!»16), p. i'.".. 



