The Influence of Environment 315 



TABLE XVlll— Continued 



These experiments indicate that the ratio of 



CNa+K 



CCa+Mg 



remains very neariy constant with varying concentra- 

 tions of ^Na+K. 



In former experiments on jellyfish the writer had 

 shown that there exists an antagonism between Mg 

 and Ca^ and this observation was subsequently con- 

 firmed by Meltzer and Auer^* for mammals. It was 

 observed that in a solution of NaCl+KCl+MgCU 

 the larvae of the barnacle were also not able to remain 

 at the surface for more than a few minutes, while an 

 addition of some CaCU made them swim permanently 

 at the surface. Various quantities of MgCU were 

 added to a mixture of m/4 or m/2 NaCl+KCl, to find 



' Loeb, J., Jour. Biol. Chem., 1905-06, i., 427. 



* Meltzer, S. J., and Auer, J., Am. Jour. Physiol., 1908, xxi., 400. 



