REVIEW OF BESREDKA'S STUDY. 285 



agglutinin of one normal serum can still take up in succession the 

 agglutinin of a second, third, and even fifth serum in any order one 

 chooses. Thus the agglutinin of horse serum was still bound by 

 pigeon blood-cells which had been treated with goat and rabbit 

 serum to such an extent that the cells were unable to abstract any 

 more agglutinin from these sera. These results are only comprehen- 

 sible if one assumes a large number of different receptors for the 

 agglutinins of different sera, and it is therefore surprising to find that 

 just these experiments which harmonize so well with Ehrlich's views 

 should be given a different and complicated interpretation by Land- 

 steiner and Sturli. 



Besredka's second premise likewise does not correspond to the 

 facts. It is now three years since Ehrlich and Morgenroth (see page 

 11) demonstrated the complex nature of normal hsemolysins in a 

 number of cases; later they brought forward evidence in favor of the 

 plurality of complements. In a final study on this subject Sachs has 

 recently (see page 181) shown that in those cases in which other 

 investigators did not succeed in demonstrating the complexity of 

 normal hsemolysins only technical difficulties and experimental errors 

 were to blame. 



After this brief analysis of the principles involved, we can pro- 

 ceed to study Besredka's experiments and discuss his conclusions 

 from the same. 



The case especially investigated by Besredka deals with the com- 

 bination human blood +ambocep tor of a goat immunized with human 

 blood and guinea-pig serum as complement. If inactive human serum 

 is added to this combination, solution will be prevented, as we were 

 able to verify. From this behavior of the human serum Besredka 

 concluded that this must contain an antiamboceptor, giving the fol- 

 lowing as his reasons. 



According to Besredka the serum of each particular animal species 

 contains a single, simple "cytase " specific for this animal. This 

 author has now sought to determine whether human serum as such 

 contains an "anticytase" against the "cytase" in question; in other 

 words, whether in this case the inactive human serum contains an 

 anticytase against guinea-pig serum. The solution of this problem 

 was extremely easy for Besredka. Guinea-pig serum, as we know, 

 dissolves certain species of blood, and does so only by means of its 

 "cytase." This action is not inhibited by human serum. Hence 



