BACTERIOLYSINS AND H&MOLYSINS 99 



bodies, then we must admit that we have better 

 chances for finding fitting complements if we make 

 use of immune bodies derived from a variety of 

 animals. We would, for instance, be likely to 

 achieve better results in treating a typhoid patient 

 with a mixture of specific bactericidal typhoid 

 sera derived from a variety of animals than if we 

 used a serum derived only from a horse. For in 

 such a mixture of immune bodies the variety of 

 partial-immune bodies must be very great and the 

 chances that the complements of the human body 

 will find fitting immune bodies, and so lead to the 

 destruction of the typhoid bacilli, are greatly in- 

 creased. Ehrlich and his pupils have actually pro- 

 posed such a procedure in the use of bactericidal 

 sera for therapeutic purposes. Reasoning along 

 similar lines, namely, that the human complement 

 must fit the immune body of the therapeutic serum, 

 Ehrlich has also proposed that these bactericidal 

 sera be derived from animals very closely related 

 to man, e.g., apes, etc. 



Support for Ehrlich' s View. Besides the above 

 experiments we possess others which support the 

 theory that the immune body is not a simple but 

 a compound substance. v. Dungern had already 

 shown that, following the treatment of an animal 

 with ciliated epithelium from the trachea of an ox, 

 there were developed immune bodies which acted 

 not only on the ciliated epithelium, but also on the 



