It is pointed out that the dehydrocholates (Decholin, dehydrocolic acid) are powerful hydrocholeretic substances. The bilirubinemia in healthy and sick individuals with unaffected hepatis parenchyma is nоt changed under their influence; in subjects with exclusively indirect hyperbilirubinemia the latter remains almost completely unaltered or it is increased but sligjtly. Direct bilirubinemia does not occur in аnу of these patients. In cases with active infective hepatitis, the dehydrocholates, applied intravenously in dosage 1-2 gr, cause augmentation of the direct bilirubin оn the secoпd hour following administration, with or without increase of the indirect bilirubln. In patients with partial mechanical obliteration of the bile routes, the direct bilirublnemia usually decreases under the influence of dehydrocholates on the second hour. Occasionally, in patients which have been ill with infective hepatitis а month or а year previously, but in the actual mоmеnt are free of jaundice and with exclusively normal bilirubinemia (of the indirect type only), а direct bllirublnemia may bе provoked under the effect of dehydrocholates on the second hour after their applicatjon. This phenomen should bе considered as manifestation of instabllized secretory functionI of the hepatic cell as regards its own bilirubin (direct bilirubin, bilirubin-glucuronide) In this respect these results could be used as basis of a test for detecting the latently developing disorders of the liver parenchyma, respectively for unhealed hepatitis. The provocation or increase of the direct bilirublnemia is conditioned bу the complex influence: firstly, of the competetive effect of dehydrocholates оn the hepatoblliar depuration of the endocellular bilirubin, secondly, bу the unstabllized directed permeabllity of the hepatic cells' membranes with view to their direct bilirubin and thirdly bу the activied hydrocholeresis.