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LECTURES ON IMMUNITY 



Regarding the nerve-poisons of the venoms, experiments 

 may be cited in which the poisons were injected intra- 

 peritoneally into guinea-pigs. The observations and calcu- 

 lations were carried out as in the case of diphtheria-poison. 

 The following values were obtained : 



NEUTRALISATION OF 0.006 G. OF CROTALUS-POISON BY MEANS OF 

 . c.c. OF ANTIVENIN 



Here I c.c. of antitoxin is equivalent to the 0.006 g. 

 of crotalus-poison. The equation of equilibrium indicates 

 that three molecules of reaction-products are formed from 

 two molecules of toxin and two of antitoxin. The con- 

 stant is K = 0.048. 



The cobra-poison was studied in the same manner. It 

 gave the following figures, which are, however, too few to 

 be used for calculation, but still indicate that the poison 

 behaves like the crotalus-poison. 



n =o I 2 34 c.c. antitoxin on 0.003 f poison. 



q (obs.) = 100 64 36 14 9 



Very peculiar results were obtained in experiments on 

 the neutralisation of the poison of the water-moccasin 

 (Ancistrodon piscivorus). There the toxicity fell to a mini- 



