3IO The Influence of Environment 



TABLE XVII 



Concentrations at which the Eggs no longer Are Able to 



Form Embryos 



In the Pure Salts 



LiCl about 6/32 m 



NaCl m/2 



KCl >ii/i6m 



<6/8 m 

 RbCl >8/8m 



<7/8 m 

 CsCl >3/8m 



<4/8m 



In the Same Salts with the Addition 



of I ex. m CaCl2 to 50 c.c. 



Solution 



>5/8ra 

 > 14/8 m 

 > 8/8 m 



>9/8m 



>8/8m 



In short it turned out that the injurious action of 

 the pure solution of any chloride (or any other anion) 

 with a univalent metal could be counteracted to a 

 considerable extent by the addition of small quantities 

 of a salt with a bivalent metal. It was also found 

 in the early experiments of the writer that the bivalent 

 or polyvalent anions had no such antagonistic effect upon 

 the injurious action of the salts with a univalent cation. 



We therefore see that what at first sight appeared in 

 the experiments of Herbst a necessity, namely, the 

 presence of each constituent of the sea water, turns 

 out as a special case of a more general law; the salts 

 with univalent ions are injurious if their concentration 

 exceeds a certain limit and this injurious action is 

 diminished by a trace of a salt with a bivalent cation. 



Why was it not possible to prove this fact for the 



