BACTERIOLYSINS AND HALMOLYSINS 79 



suggested that the curative power of many bacteri- 

 cidal sera might be increased by the simultaneous 

 injection of the sera of certain normal animals in 

 order thus to gain an increased amount of comple- 

 ment; but we shall soon see that this procedure, 

 while of great value in animal experiments, presents 

 certain difficulties. 



Nature of the Immune Body Partial Immune 

 Bodies of Ehrlich. - - Turning now to a closer study of 

 the nature of the immune body, we again find a dif- 

 ference of opinion. Whereas Bordet, Metchnikoff, 

 and Besredka assume each immune body to be a 

 single definite substance, Ehrlich and Morgenroth 

 as a result of their experiments hold to a plurality 

 of bodies. 



These authors say that each immune body 

 is built up of a number of partial-immune bodies, 

 a point to which we have already alluded. In 

 support of this view they offer the following ex- 

 periment. On immunizing a rabbit with ox blood, 

 they obtained a serum haemolytic not only for 

 ox blood but also for goat blood; on immunizing 

 a rabbit with goat blood they obtained a serum 

 haemolytic for goat blood and ox blood. 1 



The conditions present can be readily under- 

 stood by reference to Fig. 7, which represents 

 schematically three portions of the combining groups 



1 We have already called attention to these exceptions to the 

 rule of specific action. 



