BACT. PERTUSSIS AND B. BRONCHISEPTICUS 197 



nearly as well as the homologous suspension, the B. bronchi- 

 septicus. The results of such a test are given in table 2 where 

 agglutination tests were made with suspensions of fourteen strains 

 of Bact. pertussis and an homologous suspension of B. bronchi- 

 septicus against antibronchisepticus serum. And finally, table 

 3 is a summary of all the homologous and cross agglutination 

 tests. 



The results therefor show that the B. bronchisepticus antiserum 

 will agglutinate both the B. bronchisepticus and Bact. pertussis 

 antigens, while the Bact. pertussis antiserum will agglutinate 

 only its homologous antigen, the Bact. pertussis. This reaction 

 was characteristic of every strain of Bact. pertussis and B. bron- 

 chisepticus under observation. 



Whether this shows a true relationship between the two organ- 

 isms, and can be called a specific reaction, is a question. 



Preparation of the antigens for the production of the antisera. B. 

 bronchisepticus was grown on plain agar, Bact. pertussis no. 0363 (Bordet) 

 and 0590 (Ferry) on ascitic agar, and the New York strains of Bact. 

 pertussis and the hemoglobinophilic bacilli on whole-blood (rabbit) agar. 

 Twenty-four hour growths were washed off in 0.2 per cent trikresol in 

 physiologic salt solution — 1 cc. to a culture of Bact. influenzae, 2.5 cc. 

 to a culture of Bact. pertussis and 5 cc. to a culture of B. bronchisepticus. 

 The suspensions were thoroughly shaken in a mechanical shaker and, 

 after two days, tested for sterility. 



Production of antisera. Before being treated, the serum of each 

 rabbit was tested for agglutinins against all of the organisms under 

 discussion. Any animal showing an agglutination higher than 1-20 

 against B. bronchisepticus antigen or 1-40 against any of the other 

 organisms, was not used. 



The rabbits were given three intravenous injections of increasing 

 doses from 0.5 cc. to 2 cc. three days apart and were bled on the fourth 

 day after the last dose; 0.2 per cent trikresol was added to the serum 

 to insure sterility. 



Preparation of suspensions for agglutination tests. The suspensions 

 were prepared in general, as follows: 



Each culture was transplanted daily for from three days to three 

 weeks — depending upon the organism — on media best suited to it, to 

 insure a good vigorous growth. Then twenty-four hour cultures of 



