720 STUDIES IN GENERAL PHYSIOLOGY 
Two other series of experiments yielded the same results. 
It is worthy of note that the amount of a trivalent kation 
capable of exerting a certain antitoxic effect is considerably 
less than the amount of a bivalent kation necessary for the 
same purpose. At the same time one notices, however, that 
the number of eggs forming embryos is, even at the best, 
lower than when bivalent kations are employed. The reason 
for this lies, as I believe, in the fact that the trivalent ion 
causes readily a coagulation of the egg contents, as direct 
observation shows. But this coagulation is not exclusively 
a function of the valency of the ions, for Cu, Hg, and to a 
slight extent Pb have the same influence upon the egg. 
The influence of the Cr ion in bringing about coagulation 
is much more marked than is the case with Al, and its anti- 
toxic effects are correspondingly slight, but yet definite. 
TABLE XII 
Percentage of 
Solution Begs Yielding 
mbryos 
fh eeerroraree eae 100 c.c. §m NaCl 0 
ee 100 “© 4 tee. % Cr,(SO4), 3 
Bianediuwaass 100 is wo 44 is - 8 
A dos cin teaetei 100 ae “ +1 - Ke 8 
Mecgea a co seedy to 100 te ee + 2 66 &“ 10 
Gh isin’ Danan 100 “ wot 4 “ “ 6 
6. Since traces of trivalent kations and small amounts of 
bivalent kations suffice thus to annihilate the poisonous 
effects of a sodium-chloride solution, experiments were made 
to ascertain if the same could also be brought about by 
monovalent kations. The experiments have thus far led to 
no positive results. I tried to see if the poisonous effects of 
a pure sodium-chloride solution could be done away with by 
the addition of potassium salts (KCl and K,SO,). Small 
amounts of potassium salts were entirely without effect. 
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