156 



Dr. W. J. Tulloch. Tlie Isolation and 



V. 



Ahsorjytion of Agglutinin Tests. 



In order to be satisfied that the agglutination results, tabulated in 

 Diagrams I, II, and III, indicated definite antigenic differences between the 

 three types of bacilli, I carried out a number of absorption of agglutinin tests. 



Two representatives of each serological type of the bacillus were chosen for 

 this test 



Kepresentatives of Type I : — 



■ (i) A, an isolation from the U.S.A. culture, 

 (ii) C, the standard U.S.A. culture. 



Kepresentatives of Type II :— 

 (i) 2, isolated from a wound. 



(ii) 5, „ „ „ (this culture was selected because it had 



failed to agglutinate to the full titre in presence of Type II serum). 



Eepresentatives of Type III : — 

 (i) 3, isolated from a wound. 



Eacli serum was absorbed by contact with suspensiijns of each of these 

 cultures thus : — 



Three horizontal rows consisting of six centrifuge tubes were set up. Into 

 each tube of the first row was pipetted 0'05 c.c. of Type I serum : into those 

 of the second row 0"05 c.c. of Type II serum, and of the third, Type III 

 .serum. 



There was then added to each tube in the vertical columns (consisting of 

 three tubes each) 2 5 c.c. of a 2,000,000,000 suspension of baciUi, 



The tubes were incubated at 37° C. for 24 hours, centrifuged, and the clear 

 supernatant fluid from each was then distributed into agglutination tubes in 

 such dilution that with the addition of bacillary suspension the concentration 

 of the sera in each series would be 1/100, 1/200, 1/400. 



The absorbed serum in each case was used for agglutinating suspensions 

 both of the homologous bacillus and the test bacillus. 



(ii) 6, 



{d) „ „ 4, „ 5. 

 (e) „ „ 5, „ 3. 



(/■) . „ 6, .„ 6. 



