POISONS 67 



action appears identical, serum injections or gradu- 

 ated direct inoculations confer immunity towards 

 one species or a few allied species only. Thus, a 

 European in Australia who had become immune 

 to the poison of the deadly Notechis scutatus, 

 manipulating these snakes with impunity, and 

 was under the impression that his immunity ex- 

 tended also to other species, when bitten by a 

 Denisonia superba, an allied Elapine, died the follow- 

 ing day. In India, the serum prepared with the 

 venom of Naia tripudians has been found to be 

 without effect on the poison of Naia bungarus, the 

 two species of Bnngarus, and the Vipers Vipera 

 russelli, Echis carinatus, and Lachesis gramineus. 

 Vipera russelli serum is without effect on Colubrine 

 venoms, and on those of Echis and Lachesis, In 

 Brazil, serum prepared with the venom of Lachesis 

 lanceolatus has proved to be without action on 

 Crotalus poison. These examples, and others which 

 could be given, show that the hopes which were 

 at first entertained as to the benefits to be conferred 

 on mankind by the serum treatment were somewhat 

 over-sanguine — at least as regards countries like 

 India, where, different kinds of poisonous snakes 

 occurring together, it is sometimes impossible to 

 know by which the bite has been inflicted. 



Chemistry teaches that snake venoms consist for 

 the most part of solutions of modified proteids, and 

 all attempts to separate the toxic principles from 



