76 



ROPIXESS I.\- WATTLE BARK IXFUSIONS, 



Certain of the tests were examined by plate cultui'e from time to time, and it 

 was found that Al was pure on the 1st and 4th days. Phase B2 was pure on 

 the 12th daj-. Phase A2a appeared to be a mixture of Al and A2. Phasj A2 

 seemed to \k- influenced in its persistence by the salt. In the sodium lactate test 

 it was pure on the 12th day, in the citrate it contaLued a few of Al tm the 7th 

 day and on the same day the sodium chloride test consisted chiefly of Al. 



In the presence of sodium acetate and of calcium nitrate, not only was 1 here 

 no sUme formed, but there was a complete absence of growth, a circumstance 

 which led to the examination of the influence of the acetate ujiou the production 

 of ropiness in bark extracts infected with rope-producing organisms. 



The quantity of dextrose in the medium did not seem to affect the results to 

 any degTee, for the medium was strengthend with 3 ^r of dextrose and seeded 

 with Al. Calcium chloride gave a slight and fugitive ropiness on the 1st day 

 and citrate gave a fugitive ropiness on the 2nd day. All the other tests were 

 negative . 



As the activity of the saline constituents appeared to be of importance, espe- 

 cially in regard to the nmtation of the organism, another test was made. In this 

 the dextrose was used in 2 % strength with meat-extract 0.2.5 %, and the salts as 

 before, viz., 0.1 % of the anhydrous salt. The infecting phases liad been taken 

 from typical colonies two days before the experiment was started. 



On the seventh day some of the tests were plated with the Inllciuitig results: — 

 Al (succinate), typical colonies of Al. 

 A2 (sod. lactate), colonies of Al with stippled centres. 

 A2a (control), a mixture of colonies of Al and A2. 

 B2 (magn. sulph.). colonies of Bl, some with stippled centres. 



