The last decade, remarkable for its many notable discoveries of importance, has been featured by the advancement in our knowledge of the physiology of the biliary tract and by the introduction of new methods of diagnosing and treating its states of disease. As an outcome of Abel and Rowntree's1studies with the phthaleins, the discovery and development of cholecystography by Graham and Cole2marked a most important forward step. By means of it, we have been better able to study the gallbladder itself in health and disease, to estimate its function in several directions, and to increase our ability to separate the surgical from the so-called medical gallbladder. During the three years since the discovery was announced that certain halogenated dyes when given intravenously permitted direct visualization of the gallbladder by the roentgen ray, cholecystography has been steadily perfected and made safer by its originators, and has been