118 BACTERIAL ORIGIN OF GUiMS OF ARABIN GROUP, 



would be a smaller number, because the acids normall}'- present 

 in the extract are undoubtedly included. As the chief nitro- 

 genous nutrient of the boiled potato extract is asparagine, I 

 determined to employ it in media for the confirmatory tests. 

 Accordingly, solutions containing saccharose, 50 grm.; aspara- 

 gine, 3 grm.; potassium phosphate, 2 grm.; potassium chloride, 

 5 grm.; chalk, 10 grm. and tap-water 1000 c.c. were, after sterili- 

 sation, infected with the bacteria and allowed to stand in a 

 cupboard at the ordinary room temperature for three weeks. 

 In the culture of Bad. acacicB the chalk granules, on shaking 

 the flask, floated about loosely in the fluid, while with Bad. 

 metarahimun the chalk and slime cohered together in one mass. 



The culture of Bad. acacice was boiled under an inverted 

 condenser with 4 grm. of barium hydroxide for two hours- 

 The filtrate from the sediment was then distilled in a partial 

 vacuum until one-third had passed over. The distillate was 

 again distilled until one-third had distilled. The process was 

 continued until about 10 c.c. of distillate were obtained. This had 

 a smell of ammonia, which was removed by distilling with a 

 few drops of phosphoric acid. Ultimately one c.c. of a fluid 

 which showed the alcoholic tear-drops and boiled at 80° was 

 obtained. From this a few drops of a liquid which boiled at 

 78*^ were obtained by distilling M^ith anh3Tlrous sodium carbonate. 

 The liquid burned with a blue flame, and had the odour of 

 ordinary ethyl alcohol. The residues obtained during the dis- 

 tillation save the iodoform reaction with the characteristic 

 microscopical appearance of iodoform. 



The culture of Bad. metarabinum was heated on the steam 

 bath with barium hydroxide as the viscous nature of the solution 

 negatived any suggestion of boiling. Otherwise the process was 

 a repetition of that to which the culture of Bad. acacioi had 

 been subjected, and as with Bad. acaciw the culture of Bad. 

 metarabinum yielded a few drops of ethyl alcohol. 



The residual liquid from the first alcoholic distillation was 

 evaporated down nearly to dryness, and when cold added to 

 the barium-calcium carbonate sediment which had meanwhile 



