POISON OF SOME INDIAN VENOMOUS SNAKES. 67 



At 37 voluntaiy moveiiient&' 

 occurred in legs of Frog 2. 



The brains of both frogs de-' 

 stroyed. 



4.58 7-5 16-5 



May 21st. — The sciatics of the other legs were exposed and 

 irritated. 



11*5 Frog 1, no contraction. Frog 2,. 



slight contraction. The irri- 

 tability of the muscles was 

 now tested by single induced 

 shocks applied to them. 



7*5 Frog 1, no contraction. Frog 2^ 



slight contraction. 



The disturbing effects occasioned in the other experiments by 

 the necessity of comparing a limb acted on by the poison, but 

 retaining its blood-supply, with one in which the circulation 

 had been arrested, is here got rid of by employing two frogs of 

 as nearly as possible the same size. The paralysis of nerves 

 caused by the poison is evident. 



Experiment XLIII. 



December 4th. — Right leg ligatured, with the exception of 

 the sciatic nerve ; a small quantity of alcoholic extract of cobra- 

 poison dissolved in water injected into the dorsal lymph-sac. 



Noon. Injection made. 



1.30. The frog lies quite helpless. A spark of electricity 

 applied to the side causes reflex contraction of both legs. When 

 the poisoned leg is drawn out, the frog draws it up again with a 

 (95) F 2 



