Effect of Magnesium upon Frog Muscle. 67 



process. Very instructive in this connection is the work of 

 Woglom. The spleen extirpated and then inoculated subcutane- 

 ously into the same animal induces resistance against growth of 

 tumor. Extirpation of the spleen does not induce any resistance. 

 If resistance is caused in this case by the live functions of the cells 

 of the spleen, then they can act most effectively when the spleen 

 is in situ, and the mice ought to have been naturally resistant. 

 The explanation forces itself on one's mind that the spleen trans- 

 ferred under the skin is autolyzed or undergoes some other similar 

 change. 



That autolysis may be one of the means to which the organism 

 resorts in order to elaborate protective substances, is shown by the 

 very interesting investigations of Blum. He demonstrated that 

 products of autolysis of normal tissue possess the power to neutral- 

 ize tetanus and diphtheria toxins and cobra venom, and it is possible 

 to save animals from death by injecting the products of autolysis 

 subsequent to the injection of toxin. 



This investigation is still in its beginning. Different tissues 

 are tried and different methods employed to liberate the endocel- 

 lular ferments. But the view-point, while new, seems to be cor- 

 rect and capable of stimulating further research, and it is therefore 

 deemed advisable to give this short preliminary report of the pres- 

 ent state of this investigation. 



39 (449) 



The inhibitory effect of magnesium upon indirect and direct 

 irritability of frog muscle and the antagonistic action 

 of sodium and calcium upon this effect. 



By DON R. JOSEPH and S. J. MELTZER. 



[From the Departinent of Physiology and Pharmacology of the Lab- 

 oratories of the Rockefeller Institute for Medical Research^ 



Several series of experiments were carried out on frogs. In 

 the first series magnesium chloride was injected into a lymph sac 

 and subsequently nerve and muscle were stimulated at various 

 times by induction shocks. Of the results obtained two will be 

 mentioned : One is that indirect irritability gradually disappeared 

 completely while direct irritability remained practically unchanged, 



