It is generally held that congenital cystic disease of the lung is of bronchial origin. However, since Virchow1first described a similar lesion, thought to be of lymphatic origin, 21 such cases have been reported in the world literature. We wish to add two additional cases, one of which presents an unusual association of lymphatic cystic dilatation in other body organs. As is often the case with new lesions, there are divergent points of view as to their etiology and the terminology to be applied to them. Laurence2described congenital cystic disease of the lung as congenital pulmonary cystic lymphangiectasis, Giammalvo,3as congenital lymphangiomatosis of the lung, and Maidman and Barnett,4as congenital dilatation of pulmonary lymphatics. It is apparent from a review of all cases that this entity, no matter by which name it is called, must be included with other disease processes responsible for