31 - 



dextrose agar slant tubes were inoculated from the same colonies, 

 with the following results: 



Table III. 





A comparison of the five-day sugar- free agar growth shows 

 B. plymouthensisl and B. rutilus' to have been apparently 

 greatly benefited by the rejuvenating process, B. kiliensis and 

 B. plymouthensis II as adversely affected, and the others as 

 not affected at all. This may be due in part to the fact that no 

 particular attempt was made to wait for colonies showing the 

 highest pigmentation, but only to inoculate both tubes from the 

 same colony. 



When we compare the results of 24 hours for the two agars, 

 we find some interesting differences; the cultures are divisible at 

 once into two classes. B. prodigiosus I, B. ruber indicus I 

 and II, B. ruber balticus, B. ruber miquel, B. rutilus, and 

 B. amyloruber, all show more pigment on sugar free agar. With 

 the exception of B. ruber miquel, which was thin on sugar free 

 agar, the development was of about the same degree of luxuriance 

 on all. Three other cultures , B. plymouthensisl and II and 

 B. miniaceus, gave a surprising result in comparison with the others, 

 maximum pigmentation with green luster upon the sugar medium, 



1) Later, more luxuriant and darker pigment on glucose agar. 



