The Lungs and Air Passages
The lungs and air passages seen from the front. On the left of the figure the pulmonary tissue has been dissected away to show the ramifications of the bronchial tubes. Labels: a, larynx; b, trachea; d, right bronchus. The left bronchus is seen entering the root of its lung.
Martin, H. Newell & Martin, Ernest G. The Human Body: An Account of Its Structure and Activities and the Conditions of its Healthy Working (New York: Henry Holt and Company, 1917) 388