COMPLEMENTIBILITY OF THE AMBOCEPTORS. 



237 



blood-cells loaded with amboceptors, 1 by filtration through porous 

 filters, 2 and by the action of a partial anticomplement. 3 But it 

 does not in all cases require even these methods of separation; all 

 that is necessary is a thorough and continued study of the constituents 

 of the native serum of a given species. Variations can thus be observed 

 therein which lead at once to the view of a plurality of complements. 



After several years' observation we found horse serum to be 

 of especial interest in this respect, and we shall therefore briefly 

 discuss the complements of this serum. 



Horse serum is particularly well adapted for complementing 

 experiments, because, as a rule, it exerts but slight haemolytic effect 

 by itself. Sheep blood, ox blood, goose blood, and others, so far 

 as we know, are not dissolved at all by horse serum, while so far as 

 guinea-pig blood and rabbit blood are concerned there is an extraor- 

 dinary amount of variation, some horse sera exerting considerable 

 hsemolytic effect on one or both of these blood species, others having 

 no effect whatsoever. In this respect not*only did the sera of different 

 horses behave quite differently, but we also observed marked chrono- 

 logical variations in the serum of one and the same normal horse. 

 These show how much the ha^molytic properties of an individual's 

 serum can vary. The behavior of the serum (always examined in the 

 fresh condition) on the different days is seen in the following table: 



TABLE III. 



1 Ehrlich and Sachs, 1. c. 



2 Ehrlich and Morgenroth, page 56; E. Neisser and Doring, Berl. klin. 

 Wochenschr. 1901, No. 22. 



3 Marshall and Morgenroth, pages 222 et seq. 



