262 VENOMOUS SNAKES AND THE PHENOMENA OF THEIR VENOMS 



unheated venom solutions did. Heating of the immune serum to 55° C. 

 for 30 minutes did not affect its precipitating quality and quantity. The 

 reaction appeared with the dilutions down to 0.001 per cent, but not with 

 0.0001 per cent. 



The precipitin tests made with the venoms of Bungarus fasciatus, Notechis 

 scutalus, and Echis carinata were all negative, namely, no precipitate was 

 formed with these venoms. 



The above experiments of Lamb clearly point out that the proteids of two 

 entirely different snake venoms, both from the physiological and zoological 

 standpoints, can eventually be identical; hence these proteids can have no 

 relation to the real toxic components of these venoms. While a venom of a 

 colubrine snake (cobra) and that of a viperine snake (daboia) may have 

 similar proteids, it does not follow that all viperine venoms are similar in 

 this regard. On the other hand, Lamb found that the venoms of two colubrine 

 snakes (Bungarus fasciatus and Notechis scutatus) did not contain any pro- 

 teids which could react with the cobra anti-serum. Echis carinata, a viper, 

 also has no corresponding proteids with those existing in the venoms of cobra 

 and daboia. 



In a subsequent communication Lamb 1 extended the precipitin test to 

 various venoms representing practically the entire class of Ophidia. The 

 immune serum used as the precipitin was prepared in rabbit by repeated 

 injections of pure unheated cobra venom. With this cobra anti-serum he 

 obtained the following results: 



CoLTJBKma:: Coltjbeidje: 



Elapina : Hydrophina : 



Naja tripudians + Enhydrina valakadien X 



bungarus o 



Bungarus caeruleus o 



fasciatus o 



Notechis scutatus o 



Vipeeid^;: Vwkbidm: 



Viperinte : Crotalinas : 



Vipera russellii + Lachesis gramineus X 



Echis carinata o Crotalus adamanteus o 



+ = strong reaction. X = weak reaction. — = no reaction. 



From the foregoing table it becomes evident that the precipitin-reaction 

 bears no relation to the zoological classification of snake, but is of the most 

 irregular nature. Neither does it seem to have any relation to the physiologi- 

 cal or toxicological constitution of the snake venom. 



Lamb also brought out the fact that the antitoxic value of antivenin has no 

 relation to the precipitin content of the serum. Three antivenins of high 

 strength have been found to possess almost no precipitating property. He 

 sought the reason for this non-occurrence of precipitation in the species of 

 the animals, holding that asses and horses are unsuitable for the precipitin 

 production. 



1 Lamb. On the precipitin of cobra venom. Lancet, 1904, II, 916. 



