250 VENOMS 



(Hoplocephaltis, Pseudechis) form a ispecial group, which is richer in 

 hcemorrhagin than are those of the Colubrid.e of the Old World. ^ 



On studying, in the case of these various venoms, the action in 

 vitro and in vivo of a purely antineurotoxic antivenomous serum, 

 such as, for example, that of an animal vaccinated against cobra- 

 venom heated to + 75° C, it is found that this serum has a very 

 decided effect upon cobra-venom, and likewise upon that of snakes 

 belonging to allied species {Naja hungarm^, Naja haje), and that its 

 action upon the other venoms is less in proportion as they contain 

 less neurotoxin. It prevents haemolysis in vitro, and suppresses the 

 effects of intoxication on the nervous system, but does not modify 

 in any way the phenomena of coagulation or of proteolysis. 



If this serum bs made to act in vitro on thoss Viperine 

 venoms that, when heatel to + 75^ C. and deprived of their 

 hgemorrhagin, remain neurotoxic, like the venom of the common 

 viper, it is found that it renders them entirely i-mosuous. There- 

 fore, in the case of all species of poisonous snakes, and perhaps 

 also in that of other poisonous animals (such as scorpions), it 

 appears that the murototic substance is one, aiii the same, and 

 always neufcralisable by an antineurotoxic serum like that of 

 animals vaccinated against cobra-venom. 



Neurotoxin being the essentially active substance in venoms, and 

 that to which the dangerous properties of poisonous snakes, as 

 regards man and domestic animals, are especially due, it is the 

 effects of this that it is most necessary to prevent. Consequently, 



• Cf. papers by George Lamb, Scientific Memoirs by Officers of the Medical 

 and Sanitary Dcpartmoits of the Government of India, New Series, Nos. 1, 3, 

 4, 5, 7, 10, 16 ; L. Rogers, I'roceedinys of the Royal Society of London, vol. 

 Ixxii., and Lancet, February 6, 1904; C. J. Martin, Intercolonial Medical 

 Journal of Australasia, August 20, 1897, April 20, 1898; Dr. Hunter, Lancet, 

 January 2, 1904 ; Dr. Tidswell, Australasian Medical Gazette, April 21, 1902 ; 

 A. Cahnette, Comptes rendus de VAcademie des Sciences, May ,2, 1904 ; Dr. 

 Vital Brazil, "Contribution a Tetude de I'intoxication ophidienne " (separately 

 published pamphlet), Paris, 1905 ; G. Bill, Intercolonial Medical Journal of 

 Australasia, July 20, 1902, 



