Toxic AND ANTITOXIC EFrrects oF Ions’ 717 
To supplement these results the following table dealing 
with the effects of a more concentrated ZnSO, solution and 
a more dilute NaCl solution than that of the previous table 
may be given: 
TABLE VII 
Pp 4 re 
Solution Boos atte 
Embryos 
a Nee eeere eee 100 c.c. $m NaCl 5 
Ds aa Gatley af “ thee. J ZnSO, 90 
Div done sess 100 ad Se dk 4 oe 80 
A ealoitee hind 100 a © 412 “7 ee 86 
Ogaxd saad 100 s ot 4 ss 88 
The remaining experiments showed a similar agreement 
in the results obtained. It is worthy of note that these 
embryos remained alive over a week, possessed an entirely 
normal circulation, and moved in the egg. 
The experiments with freshly prepared FeSO, yielded as 
striking results as the above. Only in these experiments the 
transformation of the bivalent into the trivalent Fe ion 
introduces a disturbing element. We shall see later that the 
ferric ion is apparently extremely poisonous. The addition 
of } cc. or 1 cc. of a freshly prepared % FeSO, solution 
to 100 c.c. of 8m NaCl solution annihilates the poisonous 
effect of the pure sodium-chloride solution just as com- 
pletely as the addition of the Zn ions in the previous ex- 
periment. 
Then I tried whether cobalt ions are capable of anni- 
hilating the antitoxic effects of a pure sodium-chloride solu- 
tion. The results were very clear indeed. 
Since the amount of the bivalent kation capable of exhib- 
iting its antitoxic properties was so extraordinarily small, I 
risked the attempt to annihilate the poisonous effects of a 
pure sodium-chloride solution through the addition of Pb, 
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