576 



SCIENCE 



[N. S. Vol. XLIV. No. 1138 



here just as well, since there is a far-reaching 

 parallelism between the rules of antagonism for 

 the isolated fish and the egg. Thus Loeb and 

 "Wasteneys have shown that the fish Fundulus 

 dies more slowly in a pure m/100 or m/50 KC1 

 solution than when 10 molecules of JSTaCl are 

 added to 1 molecule of KC1; while the toxic 

 action of KC1 is prevented when 17 or more 

 molecules of NaCl are added to 1 molecule of 

 KC1. 3 The writer has recently found that the 

 same fact is true for the eggs of Fundulus, 

 with this difference only, that much higher con- 

 centrations of KC1 are required to demonstrate 

 the phenomenon in the egg than in the fish; 

 and that a much wider range of antagonistic 

 salts can be used in the case of the egg than 

 in that of the fish. This difference, how- 

 ever, can easily be accounted for by the differ- 

 ence between the membrane of the egg and the 

 skin of the fish. 



The fact that the stimulating action of salts 

 upon nerve and muscle is inhibited by Ca may 

 also be due to the prevention of the diffusion 

 of the stimulating salts into the nerve or mus- 

 cle by the Ca. 4 



The writer is in no position to state whether 

 or not Osterhout's 5 interesting observations on 

 the electric conductivity of Laminaria may be 

 interpreted as diffusion phenomena, since it is 

 not possible in that object to separate the di- 

 rect action of the salts on the membrane from 

 that upon the protoplasm. The death of a 

 cell under the influence of a salt must be 

 ascribed to an action of the salt upon the 

 protoplasm, but this action can only take 

 place after the salt has been able to diffuse 

 through the membrane. 



The diffusion of certain electrolytes through 

 a membrane seems to depend in addition to 

 the osmotic pressure of the salt in solution 

 upon a second effect which the writer has called 

 the general salt effect. 6 This effect he attrib- 

 utes to a combination of the salt with certain 



3 Loeb, J., and Wasteneys, H., Biochem. Ztschr., 

 1911, XXXII., 155. 



* Loeb, J., and Ewald, W. P., Jour. Biol. Chem., 

 1916, XXV., 377. 



s Osterhout, W. J. V., Science, 1916, XLIV., 

 395. 



e Loeb, J., Proc. Nat. Acad. Sc, 1916, II., 511. 



constituents of the membrane, presumably pro- 

 teins. 



3. There are certain kinds of antagonism 

 which seem peculiar to phenomena of irritabil- 

 ity and which can not be found in phenomena 

 of diffusion. Thus the larva of the barnacle 

 are unable to swim when put into a mixture of 

 NaCl + KC1 + CaCh until some MgCh is 

 added; they are also unable to swim in a mix- 

 ture of !NaCl + KC1 + MgCl 2 without CaCL/ 

 It is not strictly correct to call this a case of 

 antagonism between Ca and Mg, since in mix- 

 tures of Cad, and MgCL (without ]STaCl + 

 KC1) the animals are no more able to swim 

 than in a mixture of NaCl and KC1 alone or 

 of NaCl + KC1 -f MgCL Either Ca or Mg 

 suffices to counteract the diffusion of NaCl + 

 KC1 through the membrane of Ftmdulus, and 

 it is not necessary to add both. The writer had 

 first observed this type of antagonism in the 

 rhythmical contractions of the jellyfish Poly- 

 orchis* and it was afterwards observed by 

 Meltzer and Auer in mammals. 9 It may be 

 peculiar to special sense organs or other animal 

 structures since the writer was not able to ob- 

 serve it in Euglena. Jacques Loeb 



The Rockefeller Institute toe 

 Medical Research, 

 New York 



THE ELECTRICAL CONDUCTIVITY OF SOLU- 

 TIONS AT DIFFERENT FREQUENCIES 



V.l ON THE MEASUREMENT OF THE TRUE AND AP- 

 PARENT ELECTRICAL CONDUCTIVITIES AND THE 

 INDUCTANCE, CAPACITY, FREQUENCY AND 

 RESISTANCE RELATIONS 



Foe the past two years the authors have been 

 engaged in a detailed study of the passage of 

 alternating currents at different frequencies 

 through solutions of electrolytes. For a 

 source of current we have used several gener- 

 ators but especially the Type B Vreeland 



7 Loeb, J., Jour. Biol. Chem., 1915, XXIII, 423. 



s Loeb, J., Jour. Biol. Chem., 1905-06, I., 427. 



s Meltzer, S. J., and Auer, J., Am. Jour. Physiol., 

 1908, XXL, 400. 



i Summary of a paper given at the IJrbana meet- 

 ing of the American Chemical Society, April 18, 

 1916. 



