The remarks which I shall make on this subject are based on the analysis of the histories of 350 gallbladder cases, which have recently been reviewed. Rather than give a statistical study involving percentages, which are often misleading, I propose to present the fundamental principles which have been elucidated. The application of these to pathologic conditions of the biliary tract I feel has aided in more accurate and, what is more important, earlier diagnoses, resulting in more rational treatment, with better end-results.
In order to form our own opinions regarding this phase, all gallbladders and, when possible, all appendixes removed at operation were subjected to routine culture between July, 1916, and July, 1920. Recently we have not been content with aerobic cultures solely, but have used partial anaerobic culture methods. In the latter, the tissue has been macerated by grinding in a mortar with fine sand, and then planted