ON SPECIFIC THERAPEUTICS. 37 



haptines or antibodies, of which the following 

 are examples : 



(1) The agglutinins, which cause clumping of 

 the cells. 



(2) The amboceptors, which play the part of 

 carriers in the action of the complement. 



(3) The opsonins, which render bacteria liable 

 to be seized by the phagocytes ; also those hap- 

 tines which are directed against the contents, 

 or metabolic products, of bacteria. 



(4) The antitoxins. 



(5) The anti-endotoxins, which are directed 

 against the endotoxins, to our knowledge of 

 which Macfadyen, whose early death the scien- 

 tific world deplores, has contributed so much. 



(6) The precipitins. 



(7) The antiferments, which are directed 

 against certain ferments of the bacterial cells, 

 e.g., pyocyanase. 



There is no doubt, however, that many more 

 haptines exist. In order to obtain an idea of the 

 extreme diversity of the phenomena which 

 cause immunity, one must look for other 

 substances whose functions are those which 

 characterise the haptines the substances, for 

 example, which prevent cell division, or those 

 which combat the biological adaptation of 



