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SUMMARY.— The activation of phosphorylase b and the inactivation of phos‐phorylase a by skin homogenates have both been demonstrated for the first time. Certain properties of the enzymes catalysing these reactions (phosphorylase b kinase and phosphorylase a phosphatase, respectively) were investigated; it was concluded that the control system in skin is similar to that of muscle and liver. The possibility of certain dermatoses being associated with defects in this system is discussed.

From the skin surface of patients, suffering from different skin diseases, (crude) sweat was obtained by thermal stimulation: Specific gravity, pH, Na, K, Ca, Cl, free and esterified phosphate, urea and ammonia were determined. Significant positive correlations appeared between specific gravity and Na or K, between H and K, Ca, urea or ammonia, between Na and K or Cl, between K and Ca or free phosphate, between Ca and ammonia and between urea and ammonia. Significant negative correlations appeared between H and Na or Cl, between Ca and Cl, between free phosphate and ammonia and between esterified phosphate and urea. The Ca and H concentrations, in addition to the Na, K and Cl concentrations, behaved as random samples from a normally distributed population. The Na/K ratio for subjects over 50 appeared to be raised; the Na/K and Cl/K ratios in psoriasis and atopic dermatitis were lowered and in chromium dermatitis raised.

Human crude sweat and sweat from a rhesus monkey (Macaca mulatta), obtained from the skin after thermal stimulation, were compared with human saliva and skin mucus from the frog (Rana temporaria) and eel (Anguilla). Mucin from all samples contained sialic acid and small amounts of lipids and protein; the polysaccharide part was essentially sulfated and contained but little hexuronic acid and hexosamine. Hydrolysed mucin fractions from all materials showed a similar amino acid composition. The skin mucins differed from other mucins in amino acid composition by the absence of threonine. Human crude sweat from the chest contained acid phosphatase, monkey sweat acid and alkaline phosphatase, frog skin mucus alkaline phosphatase and eel skin mucus acid phosphatase. Human axillar crude sweat showed a considerable alkaline phosphatase activity in addition to a stronger acid phosphatase activity than that from the chest. In atopic dermatitis no difference appeared in sialic acid content with a control group and a difference in protein content of mucin was unlikely. In this disease the significantly larger variability in free phosphate content was presumably from intra-cellular origin and that in the results of a reaction employing sulfite and heptazine indicated the importance of an investigation into lipids, containing carbonyl groups, in skin mucin.

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