STRUCTURE OF THE LUNGS OF MAMMALS. 65 



tains, by the fusion of contiguous epithelial cells.* All the 

 borders and edges of the framework of the lung projecting 

 into the lumen of the air-passages, the free borders of the 



Fig. 133 A. 



Fig. 133 A. Fundus of a peripheral infundibulum, situated imme- 

 diately beneath the pleura. From the lung of an adult Cat, injected 

 with solution of nitrate of silver. 



alveolar septa, the more compact septa of contiguous groups of 

 alveoli, the margins of the infundibular orifices, as well as the 



* The results of my researches on the epithelium of the alveoli of the 

 mammalian lung, which are here briefly given, agree in all essential points 

 with those of Elenz (Wurzburger naturwiss. Zeitschrift, Band v.), Eberth 

 (idem), C. Schmidt (De V epithelium pulmonaire, Diss. 1866), and Colberg 

 (Deutsches Archiv fur klinische Medicin, Band ii.). The existence of an 

 epithelial lining to the alveoli is positively denied by some writers, as by 

 Addison, Remak, Rossignol, Reinhardt, Schroder van der Kolk, Adriani, 

 Radclyffe Hall, Schultz, Gerlach, Williams, Waters, Deichler, Zenker, 

 Bakody, and Henle. A few, as J. Arnold and Hertz, admit an interrupted 

 epithelium, the nucleated cells of which are only present in the meshes of 

 the capillaries, but do not cover the capillaries ; whilst others, again, as 

 E. Wagner, O. Weber, L. Meier, Chrzonszczewsky, Hirschmann, Baier, and 

 Piso-Borme, describe an epithelium completely uniform in character, and 

 composed of polygonal nucleated cells lying in immediate contact with 

 each other. 



VOL. II. F 



