Toxic AND ANTITOXIC EFFECTS OF IONS 709 



of unfertilized eggs (artificial parthenogenesis). 1 Those 

 who have followed niy work on artificial parthenogenesis 

 may have noticed that from the start I aimed at bringing 

 about artificial parthenogenesis through ions. It seemed to 

 me that I could not find any better test for my idea that the 

 electrically charged ions influence life-phenomena most 

 effectively than by causing unfertilized eggs to develop 

 by slightly altering the proportion of ions contained in 

 them. I believe that all these experiments proved what I 

 expected they would prove, namely, that by slightly chan- 

 ging the proportion of ions in a tissue we can alter its physi- 

 ological properties. 



The next step taken consisted in proving that it was in- 

 deed the electrical character of the ion that determined its 

 specific efficiency. I succeeded in doing this three years 

 ago. It was known that a frog's muscle gives rise to twitch- 

 ings or rhythmical contractions when immersed in certain 

 solutions. I showed that such contractions occurred only in 

 solutions of electrolytes, and not in solutions of non-cou- 

 ductors (distilled water, various sugars, glycerin, urea). 2 

 Soon after I showed the same to be true also for the rhyth- 

 mical contractions of the Medusae. 3 From observations made 

 in my laboratory, the same fact was shown to hold for the 

 turtle's heart by Mr. Lingle, 4 and for the lymph hearts of 

 the frog by Miss Moore. 5 I am confident that this fact 

 will be proved universally. 



In the physiology of the heart one frequently encounters 

 the statement that calcium is the stimulus for the contraction 

 of the heart. I had found that a muscle is able to twitch 



1 Part II, p. 646. Archiv fur die gesammte Physiologic, Vol. LXXXVII (1901), 

 p. 594. 



2 Part II, p. 518. 



3 Part II, pp. 553 and 559. 



4 LINGLE, American Journal of Physiology, Vol. IV (1900), p. 265. 

 '> MOORE, ibid., Vol. V (1900). p. 87. 



