1. The method of differential analysis in the IR region of the spectrum has been used in an investigation of the structure of the carbohydrate part of flavonoid glycosides. This method permits the pyranose and furanose forms of the carbohydrate substituents, the α- and β-anomers of the pyranosides and other structural features characterizing the nature of the sugars in the glycosides to be determined. The method can also be used to study other glycosides — for example, hydroxyanthraquinone glycosides, furocoumarin glycosides, and cardiac and other glycosides.