The admn. of l-epinephrine, l-nor-epinephrine or privine produces diuresis in normal rats hydrated with water. Cl excretion was also increased in these animals. Saline hydration markedly delays urine excretion. Under such conditions 1-epinephrine, l-norepinephrine and privine exerted a marked diuretic action, but were without chloruretic effect. With the doses used the effects of epinephrine and norepinephrine were similar. Ephedrine, irrespective of the hydrating soln., was without diuretic or chloruretic effects.