Further experiments are reported on Lincomycin-induced cholelithiasis in guinea-pigs. The biochemical events in the bile and blood, and the chemical composition of gallstones, have been studied. The gallstones resemble human pigment stones in chemical composition. The clear hepatic bile and the normality of the bile salt--phospholipid--cholesterol equilibrium, the rise in beta-glucuronidase and hexosamine levels with the gallbladder, have reaffirmed that epithelial injury is most probably the primary lithogenic factor. Ligation of the cystic duct and the construction of a common hepatic duct-duodenum bypass did not prevent the development of acute cholecystitis, suggesting the lithogenic factor was mediated through the blood circulation and not through the enterohepatic circulation of bile.