198 VENOMS 



AVe must not, therefore, be surprised to find that such a combination 

 may take phice with the proteic substances in venom. The com- 

 bination in this case is a truly chemical one. Lecithin in its 

 natural state, or that which is normally found in serums which 

 quicken venom, such as horse-serum, even*when heated to 65° C, 

 therefore plays the })art of complement according to Ehrlich's 

 theory, or that of alexin according to the theory of Bordet, while 

 venom itself would be an anihoccptor or sensifiscr. 



This is not, however, the way in which the phenomenon should 

 be understood, for it is impossible to admit the identification of 

 heated serum or lecithin with the complementary substances or 

 alexins, seeing that the essential characteristic of the latter is that 

 they are intolerant of heat and become entirely inactive on being 

 raised to a temperature of 58'' C, or even by simply being kept 

 for a few days exposed to the air and light. "We must therefore 

 suppose, with P. Kyes and H. Sachs, that the red corpuscles them- 

 selves contain substances capable of playing the part of comple- 

 ments {endo - complement s) , and that it is with these that the venom 

 combines when quickened by the presence of lecithin or heated 

 serum, the latter only acting because it contains free lecithin. 



All substances that contain lecithin, such as bile, hot milk, or 

 cephalin, are capable of exerting the same quickening action, but 

 do not themselves possess any inherent haemolytic power. 



Cholesterin, on the contrary, represents a kind of antidote 

 to lecithin, as also to normal serums. It prevents h£emolysis of 

 the red corpuscles in a mixture of washed corpuscles and venom, 

 yet it does not in any way modify the properties of true alexins or 

 complements. 



Moreover, no correlation exists between lecithides and the neuro- 

 toxin in venoms. The combination lecithin + venom possesses hemo- 

 lytic action, but is in no way neurotoxic. Conversely, venom can 

 be freed from its groups of molecules combinable with lecithin, 

 and remain neurotoxic. 



LecitJiidc is insoluble in ether and acetone, but soluble in 



