BY R. GRElG-SMITii. 



81 



The sohible condition of the gummy matter does not appear to be stable, for 

 when it was evaporated to dryness it became insoluble, and did not again form 

 a solution with water. 



The thickened mucilage which did not contain any reducing sugars, was 

 boiled for ten hours with 5 % sulphuric acid under an aerial condenser, and 

 during the hydrolysis it was noted that, like all the bacterial gums that I have 

 examined, furfural was given off. The solution was neutralised with barium car- 

 bonate, filtered, treated with basic lead acetate, filtered, treated with sodium car- 

 bonate, again filtered, acidified with acetic acid, and evaporated. The solution 

 ivas dextro-rotatory . 



The osazone was prepared in the usual manner, and the bulk of the tar 

 was removed by percolating the dried crystals with chloroform, then by a mix- 

 ture of chloroform and alcohol, and finally with chloroform. The crystalline 

 mass was dissolved in alcohol and allowed to stand. Successive crops of crystals 

 deposited, and were removed, dried and tested for their melting points. These 

 ranged from 202° to 193°. The intermediate crops were again crystallised, but 

 in no case could crystals with a m.p. higher than 202° to 203° be obtained. 

 Doubtless they were a mixture of glucosazone, m.p. 205°, and galactosazone, 193°, 

 but the quantities were always too small to enable the pure glucosazone to be 

 obtained. It is possible that the small quantity of glucose was present in the 

 hydrolysed gums as an impurity. In testing the gum previous to hydrolysis for 

 sugar, no positive indication was obtained, but it must be remembered that only 

 a small portion was used and, while the impurity may not have been detectable 

 in a small portion, it may show itself in the bulk after hydrolysis. 



As an example of the relative amounts of crystals obtained, the following 

 weights from a half portion of the hydrolysed gum are given. 

 1st crop — 12 milligrams, 201° 



Mother-liquor evaporated and treated with chloroform, which dissolved a 

 brownish-yellow tarry matter. 



residue . . . . 22 milligrams, 181° 



The second bacterium, B2, was grown on plates of levulose asparagin tannin 

 agar and yielded a number of tough skins which Avere easily pulled from the agar 

 surfaces. It was not always possible to get the ropy material upon this medium 

 for several later attempts failed. The slime of A2 is uuich more readily obtained. 

 There was, however, sufficient slime to enable a detennination of the hydrolytic 

 li-cduets to l)e made. The rather thick emulsion, for the gum after solution by 

 the autoclave treatment became partly coagulated upon evaporation, was unsuit- 

 > lie for testing the rotary power. The osazones were precisely similar to those 

 furnished by A2. and yielded similar fractional crops of crystals melting at tem- 

 peratures ranging from 202° to 193°, showing that the hydrolytic products of the 

 sHme of B2 were precisely similar in composition to those of A2. 



The evidence goes to show that the ropy substance is essentially a dextroro- 

 tatory galactan. 



A crop of films of the B2 slime of B2 was subsequently obtained upon im 

 agar medium containing agar 2 %, saccharose 5 %, ammonium sulphate 1 %, 



