SNAKES OF CEYLON. 445 



(g) Analysis of the toxic Action — 



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



centre is the predominent agent in causing death. 

 Rogers shows that paralysis of this centre is 

 complete before that of the phrenics is complete. 



(b) The effects of the toxin operating on the centres 



in the bulb evokes a typical bulbar paralysis, 

 affecting lips, tongue, throat, and voice. 



(c) Contributes, but is a minor factor in the production 



of asphyxia. 



(2) " Hsemolysin," by destroying the red blood cells, 



contributes to the asphyxia produced by (1) (a) 

 and (1) (c). 



(3) " Hsemorrhagin , " by damaging the intima, allows 



leakage of the vessel contents and favours 

 haemorrhages. 



(h) Symptoms : The action of the venom, as tested by 

 experiment by both Lamb and Rogers, is found to be almost 

 identical with cobra poison. The respiratory centre and the 

 ends of the phrenic nerves are paralysed, and death super- 

 venes from asphyxia. On the blood it has no action in 

 reducing coagulability, but the red blood cells are destroyed as 

 in other Colubrine poisonings. The local effects are some- 

 times marked ; on the other hand, these have been so trivial 

 in some reported cases that none could be discovered. Pain, 

 at first absent, has sometimes later become a prominent 

 symptom. 



Prom the above one would expect to find the subject of 

 krait poisoning suffering in almost the same manner as in 

 cobra poisoning. One pecuharity, however, is very frequently 

 reported, i.e., violent abdominal pain. 



The fact that Elliot found submucous hsemorrhagic spots 

 in the stomach and intestines of all the monkeys he post 

 mortemed, who died from experiment with this venom, taken 

 in conjunction with the abdominal pain so frequently noted 



