f THE PHYSIOLOGY OF POISONING 189 



explained these differences by the hypothesis that, in cases of 

 rapid death, the blood had not had time to become modified by 

 the venom. 



Later on it was found by Sir Joseph Fayrer, and subsequently 

 by Halford,' in Melbourne, C. J. Martin/ in Sydney, G. Lamb,^ 

 in Bombay, and recently by Noc, in my laboratory, that the 

 venoms of CoLUBBtD^, especially those of Naja tripudians and 

 Australian species of this family, always leave the blood fluid 

 after death, jyhile, the venoms of Viperid^, on the contrary, are 

 usually, coagulant . 



On the other hand, it was observed by Phisalix,' and at an 

 earlier d^tg: by Mosso, of Turin, that the venom of Vipera berus 

 caji^f^ Jl^e |)}gpd of the dog to lose its coagulability, while, on the 

 contjrary, the :same v^nom is actively coagula.nt , as, r-^a,vds ith,e, , 

 blood of the rabbit. 



How aye these differences of action to be explained? It was 

 found by Delezenne,' who made an excellent study of the 

 phenomena following the injection of peptone, extracts of organs, 

 and other anti-coagulant substances into the organism, that those 

 of these sulastances that render the blood non-coagulable always 

 dissolve the leucocytes, and thus set at liberty two antagonistic 

 bodies which they contain. One of these substances is coagulant 

 and is found retained by the liver, while the other remains in, 

 solution in the plasma, and keeps the blood fluid after issuing 

 from the vessels. 



Now, certain extracts of organs, ricin, abrin and certain venoms 

 in weak doses, retard coagulation, while in large doses, on the 

 contrary, they produce partial or general intravascular clotting. 



It is believed by Delezenne that the explanation of this 



' Medical Times and Gazette, vol. ii., 1873. 



^ " On the Physiological Action of the Yenom of the Australian Black Snake," 

 Proceedings of the Royal Society of New South Wales, Julj', 1895. , 



^ Indian Medical Gazette, December, 1901. 

 * Comjites rendus de la Societe de Biologic, November 4, 1899. 

 ' Ibid., October 28,- 1899. 



