SNAKE ANTITOXINE. 229 



duced. CALMETTE rendered a rabbit so immune in one year that 

 it was able to receive eighty times the lethal dose of cobra venom 

 (40 mgrms.) without showing any reaction. The serum of this 

 animal was so rich in antitoxine that 5 drops (about 0'25 c.c.) 

 neutralised 1 mgrm. of cobra venom. An ass received 0*2 grm. 

 of cobra venom in three months, and another O16 grm. in two 

 months. Half a c.c. of the serum then neutralised 1 mgrm. of 

 the venom. 



The injection of 4 c.c. of this serum four hours previously 

 afforded protection against twice the lethal dose. According to 

 PHISALIX and BERTRAND, 1 however, the antitoxine to viper 

 poison is not effective until thirty-six to forty-eight hours after 

 its introduction into the body. When an absolutely fatal amount 

 of venom is injected, and then, after the lapse of an hour, 4 to 

 5 c.c. of this serum, the animal usually survives, but an hour and 

 a half is the maximum time if there is to be any reasonable 

 certainty of a cure. 



This anti-cobra serum also affords protection against the neuro- 

 toxic components of other snake poisons, and also against scorpion 

 venom and eels' blood, and to some extent against abrine, but has 

 no effect upon ricine or upon diphtheria virus, or tetanus poison. 



The serum has just the same sort of antitoxic action as the 

 true antitoxines, but, on the other hand, CHATENAY (quoted by 

 CALMETTE, loc. cit.) observed hyperleucocytosis after the intro- 

 duction of the poison into immunised animals, whereas hypo- 

 leucocytosis could be observed in the case of the control animals. 



These observations were confirmed by CALMETTE and DELBARDE. They 

 found that animal charcoal impregnated with abrine and introduced into 

 the peritoneal cavity of immunised animals was absorbed to a large extent 

 by the leucocytes, while there was practically no absorption in the case of 

 the control animals. They came to the conclusion that the leucocytes 

 produced and stored up antitoxine. 



According to PHISALIX and BERTRAND 2 normal antisera are 

 produced by the guinea-pig, horse, and hedgehog, as well as by 

 the rabbit, but not by the hen. 



Passive immunity soon disappears, but in the case of active 

 immunity the higher its degree the longer it persists. Immunity 

 can be inherited. 



Each of the three components of the poison (hsemolysine, 

 neurotoxine, and hsemorrhagine) produces its specific anti-body 



1 Phisalix and Bertrand, " Sur la proprie't6 antitoxique du sang des 

 animaux vaccines contre le venin de vipere," Comptes Rend., cxviii., 356, 

 1894. 



2 Phisalix and Bertrand, Soc. BioL, xlviii., 396, 1896. 



