The most typical form of malformation of the esophagus is imperforation or obliteration. Van Cuyck of Brussels in 1824 delivered a child which died on the third day from malnutrition. Postmortem it was found that the inferior extremity of the esophagus to the extent of about two inches was converted into a ligamentous cord. Porro describes a case of congenital obliteration of the esophagus which ended in a cecal pouch about one inch below the inferior portion of the glottidean aperture and from this point to the stomach only measured an inch; there was also tracheal communication. The child was noticed to take to the breast with avidity, but after a little suckling it would cough, become livid, and reject most of the milk through the nose, in this way almost suffocating at each paroxysm; it died on the third day. In some cases the esophagus is divided, one portion opening into the bronchial or other thoracic organs. Brentano describes an infant dying ten days after birth whose esophagus was divided into two portions, one terminating in a culdesac, the other opening into the bronchi; the left kidney was also displaced downward. Blasius describes an anomalous case of duplication of the esophagus. Grashuys, and subsequently Vicq d'Azir, saw a dilatation of the esophagus resembling the crop of a bird. Anomalies of the Lungs.--Carper describes a fetus of thirty-seven weeks in whose thorax he found a very voluminous thymus gland but no lungs. These organs were simply represented by two little oval bodies having no lobes, with the color of the tissue of the liver. The heart had only one cavity but all the other organs were perfectly formed. This case seems to be unique. Tichomiroff records the case of a woman of twenty-four who died of pneumonia in whom the left lung was entirely missing. No traces of a left bronchus existed. The subject was very poorly developed physically. Tichomiroff finds four other cases in literature, in all of which the left lung was absent. Theremin and Tyson record cases of the absence of the left lung. Supplementary pulmonary lobes are occasionally seen in man and are taken by some authorities to be examples of retrogressive anomalies tending to prove that the derivation of the human race is from the quadrupeds which show analogous pulmonary malformation. Eckley reports an instance of supernumerary lobe of the right lung in close connection with the vena azygos major. Collins mentions a similar case. Bonnet and Edwards speak of instances of four lobes in the right lung. Testut and Marcondes report a description of a lung with six lobes.