258 



Dr. C. Todd and Mr. E. G. White. [July 1, 



Days after injection of blood 



appearance of a heeniolysin for the corpuscles of Bull No. 73 as shown in the 

 following test : — 



Testing Hcemolytic Power of Serum. Bull No. 72. 

 Blood transfused on April 30, 1911. 



Foreign red blood corpuscles disappeared on May 4, 1911. 

 Test put up as usual with — 



1. Complement 1/10, - 5 c.c. 



2. Serum, varying amounts. 



3. Bed blood corpuscles of 73 (5-per-cent. washed), 0'5 c.c. 



Serum of 72. 



Date. 



0-5 c.c. 



0,0.0. 



0-1 c.c. 



0-05 c.c. 



0-02 c.c. 



1911. 















May 5 





Trace 



Nil 



Nil 



Nil 



Nil 



„ 6 





Almost C. 



Marked H. 



Trace 



Nil 



Nil 







C. 



C. 



C. 



Marked H. 



Nil 



,. 8 





C. 



C. 



C. 



Marked H. 



Nil 



„ 9 ... 





C. 



c. 



c. 



Almost C. 



Nil 



„ 11 .. 





c. 



Almost C. 





Nil 



Nil 



„ 12 





c. 



C. 



c. 



Almost C. 



Nil 



G = Complete haemolysis. H = Haemolysis. 



The above figures for the red blood corpuscles are approximately correct, 

 but no great degree of accuracy was aimed at. The question of greater accuracy 

 merely involves the counting of a larger number of squares in the Thoma-Zeiss 

 instrument, which was not considered necessary in these experiments. 



