I. By a method (described) for the detn. of dihydrocholesterol in presence of coprosterol depending on the differential solubility of the corresponding digi-tonides in methyl alcohol, it is shown that dihydrocholesterol added to the diet is not converted into coprosterol but reappears unchanged in the feces.[long dash]II. In the putrefaction of feces the degree of saturation of the sterols rises owing to formation of coprosterol from cholesterol. The total amt. of sterol remains constant. Total sterol is detd. by the digitonin method of Windaus, saturated sterols by the bromine-digitonine method of Schonheimer.