A new member of the streptomycin series has been degraded to streptidine, N-methyl-L-glucosamine and 2-hydroxymethyl-3-hydroxy-1,4-pyrone. These cleavage products indicate that the new antibiotic differs from streptomycin only in having a hydroxymethyl group instead of a methyl in the streptose portion of the molecule. In a preliminary note we reported the isolation of a new member of the streptomycin series of the composition C21H39N7O13 produced by a new species of Streptomyces, S. griseocarneus, obtained from a Japanese soil. Since the new antibiotic differed from streptomycin by only one hydroxyl group, it was given the name "hydroxystreptomycin." In the present paper are given the details of that work along with some data on the paper chromatography of the streptomycins. The cleavage of dihydrohydroxystreptomycin with methanolic hydrogen chloride gave streptidine and a disaccharide isolated as the hexaacetate (I). Under similar conditions dihydrostreptomycin yields streptidine and a pentaacetate. The extra hydroxyl group indicated by the acetyl determination on the hexaacetate was shown not to be in the glucosamine portion of the molecule by the isolation of a pentaacetyl N-methyl-α-L-glucosamine identical with the pentaacetyl derivative from streptomycin. That the extra hydroxyl is located in the streptose moiety was demonstrated by alkaline degradation of hydroxystreptomycin to the pyrone (II) which is an isomer of kojic acid (III). The corresponding product from streptomycin is maltol (IV). On the basis of these studies the formula (V) is indicated for hydroxystreptomycin. As paper chromatography proved to be so useful in detecting the new streptomycin we show in Figs. 1 and 2 some separations of the various streptomycins to assist future workers in the characterization of the members of this growing group. In the figures streptomycin is designated as A, mannosidostreptomycin as B and hydroxystreptomycin as C. In a recent note, Grundy and co-workers have described the isolation of a streptomycin which appears to be identical with hydroxystreptomycin. Their antibiotic was produced by a Streptomyces isolated from a soil sample collected at North Chicago, Illinois. cis-2-Aminocyclohexanol on treatment with nitrous acid undergoes a pinacol rearrangement, yielding both cyclohexanone and cyclopentylmethanal. The trans epimer yields almost exclusively cyclopentylmethanal. Possible mechanisms are discussed in relation to configuration and conformation. Aminocyclanols often give anomalous high Van Slyke amino nitrogen values, which cannot be accounted for by reaction of an intermediate carbonyl compound, diol or epoxide with excess nitrous acid.