Ladd and Gross1defined duplications of the alimentary tract as "... spherical or elongated hollow structures, which possess a coat of smooth muscle, which are lined by a mucous membrane, and which are intimately attached to some portion of the alimentary tube." The most comprehensive study of these lesions thus far published was made by those authors. These cysts have been given different names, such as "enterogenous cysts," "enteric cysts," "enterocystomas," "inclusion cysts," "ileum duplex," "giant diverticula," and "gastrogenous cysts." None of these, however, is satisfactory enough to be used as a common designation for all these similar abnormalities of common embryologic derivation or developmental aberrations, regardless of location. The term, "duplications of the alimentary tract," preferred by Ladd and Gross, seems to be the most satisfactory. Lesions of this type have been encountered in all levels of the digestive tract, from the base of the tongue to the anus.