70 



The antagonistic action of salts upon the germination 

 of fungus spores as here recorded may be, in some cases, ex- 

 plained by considering that both the salts are taken up by 

 the protoplasm but that th<^ adsorption of the toxic salt 

 was so retarded by the other salt that the amount taken up 

 was below that necessary to inhibit the vital activities. 

 In the case of Gu(NC3)2it was found that the amount of 

 Ca(N02)2 necessaryto inhibit the toxicity of the copper 

 salt varied with its concentration. This variation ranged 

 from a molecular proportion of 5Ga to 8 Cu with a low con- 

 centration of Cu(NC3)2 to 6 Ca to 1 Cu at a relatively high 

 concentration. If it is assumed that the salts in the solut- 

 ion are first adsorbed by the plasma membrane or form ion- 

 proteid compounds therin and diffuse thence into the inter- 

 ior, and also that the amount of salt adsorbed is directly 

 proportional to the concentration of its solution and to 

 the time during which it acts, then it is quite concievable 

 that a higher proportion of the calcium salt would be re- 

 quired to inhibit the toxic effect of a higher concentration 

 of Gu(NC3)2. For if the proportion of the- slightly toxic 

 calcium salt to that of copper was greater the ratio of the 

 calcixxm to the copper adsorbed by the spore would be greater 

 and the total quantity of the copper salt adsorbed in a 

 given time might be no more than at one of the dilute con- 

 centrations of copper salt alone in which the spores ger- 

 minated. \7ith the combination of Pb(NG3)2 and Ca(NG3)2 this 

 reasoning could not hold as the same molecular ratio of 



