722 STUDIES IN GENERAL PHYSIOLOGY 
bivalent kation, but the life of the embryos was very con- 
siderably prolonged. 
The shortness of the spawning season limited the number 
of my experiments, so that I decided to bring my experi- 
ments upon the annihilation of the poisonous effects of a 
pure sodium-chloride solution to a close, and to carry the 
remaining experiments only far enough to decide if we are 
dealing here, in the main, with the same condition of affairs. 
That, I believe, is undoubtedly the case, so that I feel my- 
self justified in making the following statement: The salts 
of monovalent kations (Na, Li, K, NH,) with monovalent 
anions (Cl, NO,, CH,COO) exert a toxic effect at certain 
concentrations. This toxic effect can be annihilated through 
the addition of a small amount of a salt having a bivalent 
kation. For NaCl, proof has been brought forward that 
trivalent kations exhibit even a much more energetic anti- 
toxic effect than bivalent kations. Further experiments 
are yet to be made, to decide if the poisonous effects of the 
other salts (LiCl, KCl, NH,Cl) can also be done away with 
through the addition of such small amounts of trivalent ka- 
tions as suffice for NaCl. 
8. While the preceding experiments show an undoubted 
influence of the valency of the ions upon their antitoxic 
effects, it was now necessary to prove that the sign of the 
electrical charge was the second determining variable. I 
instituted a large number of experiments in which I 
attempted to annihilate the poisonous effects of a £m NaCl 
and a $m KCl solution by the addition of salts having a 
univalent or bi- or trivalent anion. The antitoxic effects of 
the following salts are investigated; KOH, NaBr, Nal, 
NaHCO,, Na,CO,, NaSO,, Na,HPO,, sodium citrate, 
K,SO,. Extensive quantitative experiments were made 
with Na,SO,, K,SO,, NaHCO, and Na,HPO,. The 
results were negative throughout. In the best cases 1 per 
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