716 STUDIES IN GENERAL PHYSIOLOGY 
TABLE V 
Percentage 
Solution of Eggs Yielding 
Embryos 
TD veatessisie- veg a 4 100 cc. §m NaCl 0 
Dass 100 “ * +tee. 2% BaCl, 8 
Di casaonods 10 « “© 4] « « 4 
ERE LE 10 « «© 49 « 4 27 
Gaee 100 “« «© +4 « & 76 
EG 100“ “ +8 « & 5 
Since all these ions are related chemically, the objection 
was possible that we were dealing here, not with the effects 
of the valence or the electrical charge of the ions, but with 
a specific chemical effect. It was, therefore, necessary to 
show that the same effect can be produced by bivalent kations 
which lie outside of the calcium group. My first experi- 
ments failed me, since I at first employed too large amounts 
of the antitoxic salts. I discovered only gradually that the 
poisonous effects of a sodium-chloride solution may be 
annihilated by a bivalent kation in quantities much smaller 
than are given in Table IV, which presents the results of one 
of my first experiments. My experiments now succeeded. 
4, A large number of experiments were performed with 
ZnSO, as the antitoxic substance for NaCl. The NaCl 
solution used was somewhat more concentrated than that 
usually employed, namely 4} m instead of Sm. 
TABLE VI 
Percentage of 
Solution Eggs Yielding 
Embryos 
EL Ae serge 100 c.c. }4m NaCl 0 
Dre caeseey 100 ee “ + hee. pty ZnSO, h 
ee oe 100 = oo +) se i 2 
he Sa renecdrartusaate 100 e “ +2 « ss 22 
Dike k-manes 100 e « 44 ee ee 50 
Ox.dt eae 100 os “« +8 75 
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