The bronchial tree and pulmonary artery of the tamandua (Tamandua tetradactyla) lung--an important example supporting the fundamental scheme for the bronchial ramification of the mammalian lung.
The lungs of a tamandua were examined on the basis of the scheme proposed for the fundamental structure of the bronchial ramification of the mammalian lung. The right lung has the dorsal, lateral, medial and ventral bronchiole systems, whereas the left lung has the dorsal, lateral and medial bronchiole systems. Three kinds of upper lobe bronchioles and a middle lobe bronchiole are present on both sides. In addition, the right lung has an accessory lobe bronchiole. The remaining bronchioles constitute the lower lobe on both sides. The right pulmonary artery runs obliquely across the ventral side of the tracheal bifurcation and reaches the ventral side of the origin of right upper lobe bronchiole III. It then runs along the right bronchus, between the dorsal and lateral bronchiole systems. The left pulmonary artery runs across the dorsal side of left upper lobe bronchiole III, and then follows the same course as that of the right pulmonary artery. The fact that the three upper lobe bronchioles are present on both sides supports the author's scheme for the fundamental structure of the bronchial ramification of the mammalian lung.