In dogs (50 exps.) increased pancreatic duct pressure caused an increased rate of blood flow through the pancreas. In 2 exps. the duct pressure was measured; the results indicate that the pancreas, when secreting against an obstruction of the duct, is capable of producing pressure sufficient to cause an increase in the rate of blood flow through the glands. The mechanism whereby increased pancreatic duct pressure causes an increased rate of blood flow through the pancreas is probably of the nature of a nervous reflex.