An examination of the metabolic products of certain fucoids

IN view of the acknowledged occurrence of the hexahydric alcohol mannitol among the Fucaceae repeated attempts were made to isolate this substance from the syrups obtained as described in the preceding paper [Haas and Hill, 1929] from Pelvetia, but without success; no trace of crystalline mannitol being obtained from alcoholic solutions by careful evaporation. It was therefore decided to make fresh aqueous, instead of alcoholic, extracts of Pelvetia as well as of Laminaria digitata and Fucus serratus; the two latter stood in marked