106 



agar was prepared. The finished ascitic agar was frequently 

 tested particularly by inoculation with the whooping-cough 

 bacillus. 



On this improved ascitic agar it was found that a slight 

 growth would appear more often, but it was always m'uch 

 less than on haemoglobin agar. In the inoculations in July 

 1920 (see pp. 88—89) all the strains of Pfeiffer's bacillus as usual, 

 gave no growth on ordinary agar; nor did the strains H 2G0 — 

 281, which were tested on agar containing the ascitic fluid 

 mentioned above, without the addition of acid, grow on this 

 medium' although the whooping-cough bacillus and Gonococ- 

 cus grew well. For the other strains (H 282—313) ascitic 

 agar with corrected reaction was employed and a number of 

 them gave distinct though scanty growth on it, even in the 

 second culture. 



Similar observations were made in the inoculations of 14. 

 IX. 1920. None of the cultures which were called Pfeiffer's 

 bacilli grew in the 2nd. generation on ordinary agar. On freshly 

 prepared ascitic agar made with ,,1,023", and on which Gono- 

 coccus and the whooping-cough bacillus grew well, some of 

 the strains that in other respects must be called Pfeiffer's 

 bacilli gave a weak growth still in the 2nd. generation. 



In the inoculations on 6. III. 1920, only ordinary agar was 

 used for the diagnosis of Pfeiffer's bacillus as mentioned above. 

 Later on the same strains were tested by inoculating on agar 

 with the addition of ascitic fluid with a sp.gr. of 1,017, which 

 gave deep blue colour with the benzidin test but was not 

 visibly red. The majority of the strains gave a weak growth 

 which could be maintained for three generations. For compa- 

 rison the 5 old strains II, 5, 6, H 14 and 19 were inoculated 

 and exhibited the same growth of slight intensity. 



But there was no growth on further subculturing, for 

 which plates were used which had been kept 5 days in the 

 ice-safe, a period which according to my usual experience, 

 only slightly impairs the value of the ascitic agar as a nutri- 

 tive medium' for the microbes for which it is specially suitable. 

 Even in the presence of decided growth-promoting organisms 

 (Staphylococcus. „white air-coccus") growth was absent. 



In agreement with what is found in the literature on the 

 subject, it is justifiable, from my experience therefore, to count 



