718 STUDIES IN GENERAL PHYSIOLOGY 
TABLE VIII 
epleata o of 
Solution Eggs Yielding 
Embryos 
Laces aos 100 c.c. §m NaCl 0 
De dha wa ets 100 ss ee + lee x CoCl, 6 
Boneneesicns 10 « « 49 °° “6 9 
A sd recrag edo: 100 ee “ + 4 6c “ 9 
Deca acne 100 se “ + 8 a “ 50 
Grniindonnere 100 a “« +12 3 “ 88 
heckstasitape wes 100 ce + 5 “ “ 62 
Cu, and Hg ions. Had I not before demonstrated the anti- 
toxic effects of so poisonous an icn as the zinc ion, such an 
attempt would have appeared to me only ridiculous. With 
copper acetate and mercuric chloride I obtained negative 
results throughout, for these two ions are so poisonous indeed 
that the small amount necessary to render inert the poison- 
ous effects of a sodium-chloride solution are sufficient to 
kill the egg or cause its coagulation. With lead ions, how- 
ever, I had a distinct success. For the antitoxic salt lead 
acetate was used, and for the toxic salt, sodium acetate. It, 
was proved that the latter was slightly more toxic than NaCl. 
TABLE IX 
Percentage of 
Solution Eggs Vielding 
Embryos 
1....] 100 ce. 4m CH, Co, Na 1 
2....| 100 + hee. 7% Pb acetate 8 
3....1100 « “ ae a “ 12 
4....}100 « “ +9 « “ 23 
5...., 100 « “ +4 “ 34 
In another case 40 per cent. of the eggs formed embryos. 
The objection was here again at hand that the decrease in 
the degree of the dissociation of the sodium acetate had 
played a rdle. Although lead chloride is only very slightly 
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