MALFORMATIONS of the Eustachian tube and the middle ear without simultaneous involvement of either the external or the inner ear or both are rare. The last review of the subject was made by Marx, 1926. Since that time a considerable amount of new material has accumulated, which made another comprehensive study advisable. This seemed particularly worth while in view of the renewed interest in the operative treatment of certain ear malformations.
Pharyngeal Ostium.—Although generally the pharyngeal ostium is situated in the fetus below the level of the hard palate, at birth at the level of the hard palate, and in adults about 10 mm. above it, individual variations in the position and shape of the ostium are frequent. Overdevelopment of the tensor tympani muscle may lead to abnormal patency of the ostium (von Kostanecki). Abnormal width of the ostium is not too rare. Sometimes a recessus is