344 Action of Choline, A/eurine, Muscarine, and Betcfine. [June 12, 



FIG. 16. Choline- Atropine. 

 Ch. 



Froe's heart. Effect of choline hydrochloride at Ch., 2'5 per cent, solution in- 

 normal saline. Subsequent application of atropine sulphate, 1 per cent, 

 solution. 



FIG. 17.- BetaTne-Atropine. 



B, 



/% Betaine hydmchl: 



Frog's heart. Effect of betaine hydrochloride, 1 per cent, solution neutralised by 

 NaOH, applied at B! and B 2 . Subsequent application of atropine sulphate, 

 1 per cent, solution. 



Conclusion. The general conclusion to be drawn for the above- 

 experiments on isolated nerve and on the excised heart is that the order 

 of toxicity of the four ptomaines examined is : 



Istly. Neurine and muscarine. 



2ndly. Choline and betaine. 



