SNAKES OF CEYLON. 487 



(k) Analysis of the Action of the Toxins — 



(1) (a) The " neurotoxin " paralysing the respiratory 



centre is the predominant agent in causing death. 

 It is assisted by (1) (d), and slightly by (4) (6). 



(b) The effects of the "toxin " that depresses the vaso- 



motor centre are neutralized by the combined 

 antagonistic action of (2 ) and (3 ). The result is that 

 after breathing has ceased, artificial respiration is 

 capable of prolonging life for many hours. 



(c) This " toxin," operating on several centres in the 



bulb, evokes symptoms exactly similar to those 

 seen in bulbar palsy, where lips, tongue, throat, and 

 voice are paralysed. 



(d) Assists (1) (a) in the production of asphyxia. 



(e) The toxin " amyotrophin - ' destroys nerve cells 



generally, but its action is not seen in the human 

 being, death being brought about by the more 

 speedy action of (I) {a). When (1) (a) is insufficient 

 to cause death, the dose of " amyotrophin " is too 

 small to produce death, or even to seriously affect 

 the bitten subject. 



(2) The cardiotonic element, by reinforcing the heart 



muscle, helps to preserve the blood pressure, and 

 helps to counteract the effect of (1) (6) 



(3) The vaso -constrictor, by reducing the calibre of the 



blood vessels, raises blood pressure, and acts indirectly 

 in reinforcing the heart. With (2) it completely 

 counteracts the effect of (1) (6). 



(4) (a) The effect of the antifibrin ferment is seen in the 



reduction of clotting power in the. blood, and this 

 in conjunction with (5) (a) accounts for the haemor- 

 rhages that may occur. 



(6) " Hemolysin," by destroying red blood cells, contri- 

 butes to the asphyxia produced by (1) (a) aided 

 by(l)(6). 



