In 1904, Albrecht (1) proposed the term hamartoma for a benign mixed tumor occurring in various organs including the lung. According to him, hamartomata are not true tumors but rather tumor-like malformations due to abnormal mixing or development of the normal tissue components of the organ. This abnormality may be the result of variations in the quality, arrangement, or degree of differentiation of the tissues, or, sometimes, in all three. For a long period following Albrecht's contribution there appears to have been little interest in hamartomata, particularly those of the lung. A search through the literature, however, reveals several articles dealing with pulmonary hamartoma, incorrectly referred to as chondroma. In 1926, Hickey and Simpson (2), under the title “Primary Chondroma of the Lung,” reviewed 38 cases from the literature and reported 2 cases of their own. It is clear from their histologic descriptions that the tumors with which they dealt were typical examples of hamartoma according to Albre...