92 BACTERIOLOGY. 



out of grape-sugar, the construction that is, of 

 complicated compounds of sugar with other 

 bodies. For examples of the decomposition of 

 maltose, dextrine or starch, I may refer to p. 52. 

 The following illustration of the decomposition 

 of glucosides may be permitted : 



C^H^NOn + 2H 2 '= 2C 6 H 12 6 + C 6 H 5 .COH + HCN 

 amygdalin, water, grape-sugar, benzaldehyde, prussicacid. 

 C 27 H 22 17 + 4H 2 = C 6 H 13 6 + 3C 7 H 6 5 

 tannic acid, waterj grape-sugar, gallic acid. 



According to , recent synthetic work, the 

 polysaccharides, such as starch, dextrine, cane- 

 sugar, malt-sugar or maltose and milk-sugar 

 are to be regarded as glucosides of the simple 

 sugars. In this connection we may note the 

 interesting fact that new carbohydrates may be 

 produced from other carbohydrates by the ac- 

 tion of prussic acid, and that prussic acid itself 

 may arise also as a decomposition product. We 

 know that prussic acid (HCN), one of the 

 most potent of the nitrogenous poisons, under 

 the influence of polymerization can become 

 non-poisonous and even available for the con- 

 struction of organic substance, as Pfliiger was 

 the first to demonstrate : for example, adenin, a 

 normal element of the cells of both higher and 

 lower organisms, possesses, according to its dis- 

 coverer Kossel, the formula H 5 C 5 N 5 , or five 

 molecules of prussic acid (5HCN). According 



