THE PHYSIOLOGY OF POISONING 193 
Halford,! Sir Joseph Fayrer,? C. J. Martin,’ Delezenne,* Phisalix,” 
and lastly Noc,f have shown that the venoms of COLUBRID exert 
a manifestly anticoagulant action upon citrate-, chloridate-, or oxalate- 
plasmas, and also upon blood mixed with venom on issuing from 
the vessels. 
On adding 1 milligramme of Cobra-, Bungarus-, Australian 
Pseudechis-, or Ancistrodon-venom to 1 c.c. of citrate-, oxalate-, 
or chloridate-plasma, and supplementing the mixture, after varying 
periods of contact, with a quantity of chloride of calcium (for the 
citrate- or oxalate-plasmas), or distilled water (for the saline 
plasma) sufficient to produce coagulation in a few minutes in the 
control tubes without venom, we find that coagulation no longer 
takes place after one hour in the tubes containing Cobra- or 
Bungarus-venom, and after ten minutes in those that contain the 
venom of Ancistrodon. 
In doses less than 1 milligramme for 1 c.c. of plasma, these 
venoms by themselves never produce coagulation as do those of 
Lachesis or Vipera russellii. They are thus sharply differentiated 
in this respect. 
If fresh blood issuing from the arteries of an animal be received 
in a vessel containing a sufficient quantity of CoLUBRINE-venom 
(that of the Cobra for example), and steps be immediately taken to 
ensure the perfect mixture of the venom and the blood, we find that 
the latter has entirely lost its coagulability, just as though it had 
been mixed with peptone or extract of leeches’ heads. 
Again, if a mixture be made in vitro of coagulant venoms, such 
' Medical Times and Gazette, vol. ii., 1873. 
? “The Thanatophidia of India.” Churchill, London, 1872. 
5 “On the Physiological Action of the Venom of the Australian Black Snake,” 
Proceedings of the Royal Society of New South Wales, July 8, 1895. 
4 Archives biologiques, 1897 and 1898; Comptes rendus de la Société de Bio- 
logie, October 28, 1899. 
5 Comptes rendus de la Société de Biologie, October 28, 1899; November 4, 
1899; July 26, 1902. 
5 Annales de V Institut Pasteur, June, 1904. 
13 
