enema. The gross and microscopic appearance of the diverticulum he described was very similar to the one in our case history, with the exception that it had a very minute orifice, which apparently acted as a valve permitting gas alone to enter the diverticulum.In our case, the diagnosis of a megadiverticulum had already been established at the time of the last admission. However, in view of the clinical history, the presence of an air fluid level in a diverticulum which had previously been demonstrated to have a broad neck, associated with a change in its position, indicated a volvulus or torsion of the diverticulum. 4833 Fountain Ave. Los Angeles 29 (Dr. Silberman).