1903.] Physiological Action, etc., of Snake Venoms. 419 



" On the Physiological Action and Antidotes of Colubrine and 

 Viperine Snake Venoms." By LEONARD ROGERS, M.D., 

 B.S., M.E.C.P., F.E.C.S., Indian Medical Service. Com- 

 municated by Dr. A. I). WALLER, F.K.S. Eeceived and read 

 November 19, 1903. 



(From the Physiological Laboratory of the London University.)* 



(Abstract.) 

 Part I. COLUBRINE VENOMS. 



The Indian Colubrine snakes other than the Cobra have been little 

 investigated since the classical work of Fayrer, Lauder Brunton and 

 Wall. Their physiological actions are dealt with in this paper. 



I. The Nam Bunga/rus or Hamadriad is the largest poisonous snake. 

 The symptoms produced by it are identical with those of Cobra venom, 

 and its toxicity is very similar in degree to it. 



Its haemolytic action is very slight compared to that of the Cobra, 

 its power in this respect being only about one-hundredth that of the 

 latter. 



Blood-pressure and respiratory curves of this and the other venoms 

 dealt with in this paper have been taken in the case of cats and rabbits 

 by means of a Gad's manometer connected with a cannula in the carotid 

 artery, and a Sandstrom recorder connected with a tracheal cannula, 

 with the following results : 



In Experiment I a dose of 5 milligrammes per kilogramme produced 

 paralysis of respiration in 1J minutes, followed by circulatory failure 

 of a secondary nature in 2 minutes. In Experiment II 1 milligramme 

 per kilogramme produced a temporary stimulation of respiration followed 

 by complete failure in 10 minutes. In Experiment III a very similar 

 result was obtained, while, in addition, it was found that by means of 

 artificial respiration the circulation could be kept going long after total 

 cessation of breathing. In each case the motor end-plates of the 

 diaphragm were paralysed at the end of the experiment, but by means 

 of stimulating the nerve at intervals during the experiment it was 

 found that this paralysis did not take place until after that of the 

 respiratory centre. 



The action of Hamadriad venom then, in all respects, resembles 

 that of the Cobra, with the exception that it has very little hsemolytic 

 action. 



II. The Bunyarus fasciatus or Banded Krait, although a large snake, 

 has always been considered the least deadly of its class in India. The 

 symptoms which it produces are very similar to those of the rest of 



* A grant in aid of this research was received from the Boyal Society. 



