543 
Rabbit i and from Rabbit 896 (infected with 7 . dimorphon ), and a 
5 per cent, suspension of washed erythrocytes from the following- 
animals: normal Rabbits 1 and 2, Rabbit 8 q 6 and a normal horse 
and guinea-pig. 
From the results of this experiment, details of which arc given 
in Table IV, and from other observations of the same kind one is 
led to conclude that in the blood of infected animals, in addition 
to an excess of auto-agglutinin, there is also frequently a 
corresponding increase in iso- and hetero-agglutinin. 
The question now arises as to whether these reactions are 
manifestations of the same body or of different specific agglutinins. 
Hie procedure usually adopted for the solution of problems of this 
nature is the saturation of a portion of the serum by the red cells 
"f one of the varieties in question, and then, after allowing reaction 
to take place for some hours, centrifugalising and examining the 
extracted serum regarding its agglutinating action on the red cells 
of the kind used for extraction and also on the other varieties of 
erythrocytes. 
Malkoff, adopting this technique, arrived at the conclusion that 
there exist in goat’s serum, which is capable of agglutinating the 
erythrocytes of many kinds of animals, different specific agglutinins, 
each of which has a specific affinity for the corresponding variety 
of red cells. 
Experiment. —(1) One volume of defibrinated plasma oi Rabbit 
896 (infected with T. dimorphon) was extracted for twelve hours 
at o° C. with an equal volume of the undiluted red blood cells of 
the same animal. (Extracted plasma A.) (2) Here the proportion 
of plasma to erythrocytes was one to five. (Extracted plasma B.) 
(3) One volume of the same plasma was treated with one volume oJ 
normal horse’s red cells. (Extracted plasma C.) 
A 5 per cent, suspension of washed erythrocytes was prepared 
from the following animals: Rabbit 896, normal Rabbit 1, normal 
Donkeys 1 and 2, a normal guinea-pig, horse, Macacus rhesus , 
C crcopithecus cnllitrichus , and human being. 
The results indicate that complete extraction of the infected 
plasma of Rabbit 896 by its own erythrocytes and those of a normal 
•‘Beitrage zur Frage dcr Agglutination von rother Blutkorperchen/ Deutsche Med. Woch., 
lone. Mo. 14. 
