OSCAR TEAGUE 



num. = numerous colonies. 



f. num. = fairly numerous colonies. 



Five of the paratyphoid B. cultures (Am. Boston 2, 61, 53? 

 and Roanoke) and- 2 of the B. enteritidis cultures (And. and 

 Whit.) gave intermediate results; that is, they were not inhibited 

 as completely as paratyphoid B cultures, nor did they give as 

 good growth as the paratyphoid A cultures. The paratyphoid 

 organisms are known to undergo mutations occasionally after 

 having been grown on artificial culture media for long periods of 

 time, the B type assuming characteristics of the A type and vice 

 versa. It seemed not unlikely that these few cultures may have 

 behaved atypically with regard to growth on the Victoria blue 

 agar because such mutations had occurred in them. Another 

 possibility is that they may have had their source from some 

 of the lower animals and not from infected human beings. 



Similar experiments were performed with cultures of B. 

 suipestifer, B. typhi murium and B. Danysz, the results of which 

 are recorded in table 2. 



