BACILLUS OF MORGAN 



73 



AGGLUTINATION TESTS 



Immediately after isolation of the Morgan strains agglutina- 

 tion tests had been carried out in serum from patients III, IV, 

 VI, VII, VIII, and IX with the homologous Morgan strain 

 and with B. typhi, B. paratyphi A and B dysentery I, II and 

 III and always with a negative result. 



Sera had been produced by injection in rabbits of heated agar 

 slope cultures emulsified in saline solution, and these sera had 

 been tried against the homologous and heterologous strains. 



TABLE 2 



Agglutination tests 



Lowest dilution; in first examination 1 : 50; in second 1 : 5 



Seven months later the agglutination test was repeated to 

 find out whether the growth on artificial media had altered the 

 reaction or not. 



The result of these tests are shown in table 2. 



The first column of figures gives the result of the first exami- 

 nation, the second column that of the second one. 



It will be noted that all the strains tested show a high agglutina- 

 tion titre in the homologous sera, but none or very low ones in 

 the heterologous sera. Only strain V shows some degree of 

 agglutination in a heterologous serum from strain VI, but this 

 reaction is completely extinguished seven months later. 



One year after this examination there were produced new sera, 

 living bacilli being used for the injection. The result of this 



