In a previous communication1 the differential bile acid analysis of a large series of samples of bile removed from gallbladders at operation was reported. The bile was analyzed for bile acids conjugated with taurine and with amino-acetic acid, for cholic acid, for desoxycholic acid and for free bile acids. It was shown that the point of greatest significance was the variation in the proportions of the different bile acids in any one sample. Thus, in samples of bile removed from normal gallbladders, cholic acid formed about one half of the total bile acid content, while about 20 per cent of the total was in the form of free bile acids. In cases of chronic cholecystitis, the cholic acid content averaged about 30 per cent and the free bile acid content about one third of the total bile acid content. In sharp contrast, analysis of the bile from the gallbladder