' Tin-: PHYSIOLOGY OF POISONING 189 



explained these differences l)y the hypothesis that, in cases of 

 rapid deatli, 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. Lainb,-^ 

 in Bombay, and recently by Noc, in my laborator}', that the 

 venoms of Colubrid.e, especially those of Naja tripudians and 

 Australian species of this family, always leave the blood fluid 

 after death, while the venoms of Viperid.e, on the contrary, are 

 usually coagulant. 



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

 earlier date by Mosso, of Turin, that the venom of Vipera her us 

 causes the blood of the dog to lose its coagulability, while, on the 

 contrary, the same venom is actively coagulant as regards the 

 blood of the rabbit. 



How are 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 substances 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., 187o. 



- " On tlie Phj-siological Action of the A'enoni of the AustraHan Bhick Snake," 

 Proreedinfjs of the Royal Society of Neic Soutli Walcf, July, lH9.j. 

 ■' Indian Medical Ga;^ette, December, 1901. 

 ■• Comjjfes rendus dc la Socicic dr Biohxjic, Xovcniber 4, 1899. 

 •■■ Ibid., October 28, 1899. 



