Development of the Intrasegmental Bronchial Tree: the Pattern of Branching and Development of Cartilage at Various Stages of Intra-uterine Life *

The purpose of this study is to establish the progress of branching of the intrasegmental part of the bronchial tree at different phases of intra-uterine life and the relation to it of the development of bronchial cartilage. The importance of the topography of the pulmonary segments to both the surgeon and the clinician has led in recent years to the study of the growth of the segmental structures (Boyden