374 



Mr. C. Eevis. 



[Apr. 8, 



were started in order to provide a control for any changes which might occur. 

 This procedm-e has, however, been found subsequently to be of little avail, as 

 in many cases in which two inoculations from the same cultures have been so 

 started they have not behaved in the same manner under the same circum- 

 stances. In this particular case one culture experienced much greater 

 difficulty in growing in the presence of Brilliant Green and eventually died 

 out. The other which survived was finally plated out, when it had been 

 trained to grow in broth containing 0*05 per cent, of the dye, and the organism 

 was then developing well in it. The plating out was made on ordinary 

 nutrient ( + 1) agar and the plates were kept at 20° C. 



Two types of colony arose : — (A) very small, (B) large and arborescent. 

 Both varieties grew rather slowly at 20° C. on the plates, as did also sub- 

 cultures from them. They were tested in the usual peptone water media 

 with the following results : — 



(A) Milk Acid in 7 days, but no coagulation at all. 



Lactose peptone water ... + + in 48 hours. 



Sucrose „ ... 



Adonitol „ ... 



Dulcitol „ ... *A., si. G., about the 20th day. 



(B) was very similar, but milk coagulated in 48 hours, dulcitol was not 

 attacked at all, and only A., si. G. occurred in mannitol. 



It is noteworthy that the organism which showed the greater vitality 

 (judged by growth on agar) had suffered the greater loss of fermentative 

 power. This has been found to be the rule in other cases. Both of these 

 organisms (A and B) were carried on in Brilliant Green broth (O05 per cent.) 

 but (A) soon succumbed, while (B) grew as well as before. This will now be 

 called Culture B. 



The original culture in Brilliant Green broth from which these (A and B) 

 were obtained was kept going in the same medium (Culture C) and an 

 inoculation was also made from it into Malachite Green broth (Culture D). 

 In all cases these cultures were re-inoculated into fresh tubes once a week 

 and were all kept at 37° C. 



Inulin 



Glucose 



Salicin 



+ 4- in 48 hours. 

 A., si. G., on the 7th day. 

 + in 48 hours. 



Mannitol 



Indicates acid reaction, but only very small bubble of gas. 



