THE VENOMS. 99 



Mosso has found in the blood serum of the 

 lamprey a toxin possessing a strong hemolytic 

 power, and which he has named ichthyotoxin. 0.5 

 Cc. of this serum injected into a dog kills it in 

 a few minutes. He also observed, in 1888, that 

 the blood of the eel, in like dose, kills a dog 

 almost immediately, and that the blood contains 

 an ichthyotoxin analogous to that of the 

 lamprey. 



This substance, which appears to be closely 

 allied to the sero-albumin of the blood, has a 

 phosphorus-like, sharp, and burning taste. By diges- 

 tion it loses its toxicity, as well as by heating at 

 68 to 70 C. It is easily obtained by precipitating 

 with ammonium sulphate the serum of eels, and 

 dialyzing the precipitate dissolved in water. The 

 power of this substance is almost as great as that 

 of the cobra poison, 0.002 Gm. being instantly 

 fatal per kilo of dog. 



The blood of snakes is likewise very toxic; the 

 same is true of the blood of the viper, as 0.02 Cc. 

 will kill a guinea-pig in two hours. All these 

 bloods lose their toxicity when heated above 70 C. 

 The serum of the hedgehog is peculiar in this 

 respect; when heated at 38 C. for fifteen minutes 

 it loses its toxicity, but it then possesses an immu- 

 nizing power against the poisons. 



The subject possesses great interest, because it 

 was in studying these immunizing properties that 



