Just below the mid point of the specimen there is a 2 cm pouch; the lips of the orifice are smooth and the epithelium of the oesophagus is continuous with that in the pouch. There is no ulceration. This was an incidental finding at autopsy in a man of 70; it was situated at the level of the bifurcation of the trachea. The pouch was lightly adherent to mediastinal structures. This represents a forme fruste of a congenital tracheo-bronchial fistula.