POISON OF SOME INDIAN VENOMOUS SNAKES. 93 



Experiment LXIV. 



July 21st, 1873. — A rabbit was etherised, the calvaria 

 removed, and the cerebral lobes carefully excised. The bleeding 

 was arrested by cotton-wool steeped in perchloride of iron, and 

 by the actual cautery. 



1.18. The operation concluded. 



1.23. Kespirations 32 per minute. Eeflex movements well 

 marked on pinching feet or tail. 



1.33. Eespirations 16 per minute and much deeper ; and each 

 one ended with a jerk, as if of the diaphragm. 



1.35. Fore legs extended in a convulsive manner. Eespira- 

 tion ceased almost entirely ; but at long intervals of about 

 15 and 20 seconds, an inspiration occurred. 



On pinching the feet the respiratory movements became more 

 perfect, though feeble. 



IAS. Heart beats rapidly but feebly. Eespiration has ceased. 

 Eeflex movements are still well marked. 



1.44. Cannula placed in the trachea, and artificial respiration 

 begun. Eeflex movements continued for some minutes ; but 

 then the heart ceased to beat. 



3.55. Sciatics exposed and irritated by a Faradic current. Xo 

 contractions occurred in the limbs. The muscles contracted 

 when irritated directly. 



From these experiments it was evident that the accelerated 

 respiration was not of cerebral origin ; and it was therefore 

 probably due to stimulation of the pulmonary branches of the 

 pneumogastric by the poison. If this were so, the acceleration 

 would not appear if the vagi were divided previously to the 

 injection of the poison, as the stimulation of the terminal 

 branches of the nerves in the lungs would no longer be con- 

 ducted to the medulla. The following experiment shows that 

 our hypothesis is correct, the injection of the poison rendering 

 the respirations, which had already been greatly diminished in 

 rapidity by division of the vagi, still slower. 



Experiment LXV. 

 September 15 th. — A dog was chloroformed ; both vagi were 

 divided, and a cannula placed in the trachea. On recovering 



