220 VENOMS 



condition, of fresh serum derived from other snakes, or of fresh 

 sermn from the guinea-pig. 



Antivenomoiis serum also, when added in a suitable dose, 

 entirely suppresses the haemolytic action of snake-serums ; it has, 

 however, greater effect upon the hsemolysin of (7o6?u-blood than 

 upon that of the blood of other snakes. This observation had 

 previously been made by W. Stephens,^ and it has been verified 

 by Noc in my laboratory. 



Crotalus-seYum dissolves the red corpuscles of the mongoose 

 (Herpestes ichneumon) of Jamaica, whose extraordinary resistance 

 to venom is well known. But if variable doses of Ancistrodon- 

 venom and Grotaliis-^exnm be made to act simultaneously upon 

 these corpuscles, the latter are no longer dissolved. Again, if, 

 instead of red corpuscles which are but little sensitive, like those 

 of the mongoose, we employ the highly sensitive corpuscles of the 

 guinea-pig, the result is the same. These experiments are regarded 

 by Flexner and Nognchi as proving that the amboceptors of the 

 toxic serum become fixed, in conformity with Ehrlich's theory of 

 the lateral chains, upon the receptors of the sensitive erythrocytes, 

 and leave no more receptors free for the fixation of the venom. 



The same investigators have endeavoured to determine the 

 respective toxicity of the tissues of the different organs of Crotalus. 

 They found that the most toxic organs are the spleen and the 

 liver ; the toxicity of the spinal cord, kidney and muscles is nuich 

 less. It appears that this toxicity is intimately connected with the 

 quantity of blood that the tissues retain, for the physiological effects 

 observed are identical with those that follow the injection of blood 

 or serum alone. 



They also ascertained that the contents of the eggs of Crotalus 

 are especially rich in poison, and this poison appears to consist for 

 the most part of neurotoxin, since it does not cause haemorrhages. 

 Phisalix has observed that the ovules of the viper exhibit analogous 

 toxicity .- 



' Journal of Pathology and Bacteriology, 1900, p. 273. 

 * Comptes rendus de la Societe de Biologie, July 1, 1905. 



