BACTERIOLOGY. 199 



Table V. — Showing agglutination of culture "Hongkong." 



Grown at 37° C. 



Grown at 82° C. 



2 hours. 



4 hours. 



20 hours. 



2 hours. 



4 hours. 



1 

 20 hours. 



+ + 



+ + 



+ + H- 



+ 



+ 



+ + + 



+ + 



+ + 



+ + + 



+ 



f 



+ + + 



+ 



+ -{- 



H- + + 



+ 



+ 



+ + + 



+ 



+ + 



+ + + 



+ 



+ 



++ + 



+ 



++ 



+ + + 



+ 



+ 



+ + + 



+ 



+ + 



+++ 



+ 



+ 



+ + + 



+ 



+ + 



+ + + 



+ 



+ 



+ + + 



+ 



+ 



+ + 



+ 



+ 



+ + + 



trace 



+ 



+ + 



+ 



+ 



+++ 



trace 



-r 



+ + 



+ 



+ 



+ + + 



— 



+ 



-t- 



+ 



+ 



+ + + 



— 



— 



— 



— 



trace 



+ + 



— 



— 



— 



— 



trace 



+ + 



— 



— 



— 



— 



+ 



++ 



— 



— 



+ 



— 



+ 



+++ 



— 



— 



+ 



— 



+ 



++-^ 



— 



+ 



+ 



+ 



+ 



+++ 



— 



+ 



+ 



+ 



+ 



+++ 



— 



+ 



+ 



+ 



+ 



+++ 



— 



+ 



+ 



+ 



-t- 



+ + + 



Serum of immunized rabbit: 



A 



A 



A 



rhv 



SIB 



tiv 



lAo 



»Ao 



iT^re -- 



lahui 



Salt solution 



Serum of normal rabbit: 



A 



A 



A 



rio 



sin 



sio- 



tAo 



sAo 



Salt solution 



In Table III it is seen that the strain used agglutinates at 

 greater dilutions when grown at 32 °C. than when grown at 37 °C. 

 The control tubes with normal serum show in the case of the 

 bacteria grown at 37 °C. no agglutination whatsoever, even after 

 twenty hours, while in the cases of the bacilli grown at 32 °C., 

 the bacteria have all settled out in twenty hours. 



The same strain, after passage through an animal, does not 

 agglutinate at as great dilutions as before. When grown at 32° 

 C, it also shows less tendency toward spontaneous sedimentation 

 than previous to the passage through the guinea pig. When 

 grown at 12° C, flocculation begins almost as soon in the tubes 

 with normal serum as it does in those containing immune serum, 

 so that it is difficult to determine whether or not specific aggluti- 

 nation has taken place; however, after twenty hours, on shaking 

 the tubes, the sediment in those with normal serum readily forms 

 a homogeneous suspension, while in the first few tubes, at any 

 rate of those containing immune serum, the sediment is seen to 

 consist of coarser flocculi. 



These same observations apply in a general way to the strain 

 used in Table IV. This strain, however, when cultivated at 



