224 THE LYMPHATICS OF THE LUNG. 



the volume of the lung, so that they are more flattened when the lung is distended, 

 as during inspiration (Klein). The pleura contains many lymphatics, which com- 

 municate by means of stomata with the pleural cavity.] 



[The Lymphatics of the lung are numerous and are arranged in several 

 systems. The various air-cells are connected with each other by very delicate 

 connective-tissue, and according to J. Arnold in some parts this interstitial tissue 

 presents characters like those of adenoid tissue ; so that the lung is traversed by a 

 system of juice-canals or Saft-canalchen.] [In the deep layer of the pleura, there is 

 a (a) sub-pleural plexus of lymphatics partly derived from the pleura, but chiefly 

 from the lymph-canalicular system of the pleural alveoli. Some of these branches 

 proceed to the bronchial glands, but others pass into the interlobular septa, where 

 they join (b) the peri-vascular lymphatics which arise in the lymph-canalicular 

 system of the alveoli. These trunks, provided with valves, run alongside the 

 pulmonary artery and vein, and in their course they form frequent anastomoses. 

 Special vessels arise within the walls of the bronchi and occur chiefly in the 

 outer coat of the latter, constituting (c) the peri-broncliial lymphatics, which 

 anastomose with b. The branches of these two sets run towards the bronchial 

 glands. Not unfrequently (cat) masses of adenoid tissue are found in the course 

 of these lymphatics (Klein)]. The lymph-canalicular system and the lymphatics 

 become injected when fine coloured particles are inspired, or are introduced into 

 the air-cells artificially. The pigment particles pass through the semi-fluid cement 

 substance into the lymph-canalicular system and thence into the lymphatics 

 (v. Wittich) ; or, according to Klein, they pass through actual holes or pores in the 

 cement (p. 221). [This pigmentation is well seen in coal-miners' lung or anthra- 

 cosis, where the particles of carbon pass into and are found in the lymphatics. 

 Sikorski and Kuttner showed that pigment reached the lymphatics in this way 

 during life. If pigment, China ink, or indigo carmine be introduced into a frog's 

 lung, it is found in the lymphatic system of the lung. Euppert, and also 

 Schottelius, showed that the same result occurred in dogs after the inhalation of 

 charcoal, cinnabar, or precipitated Berlin blue, and von Ins after the inhalation of 

 silica. A. Schestopal used China ink and cinnabar suspended in f p.c. salt 

 solution.] 



Excessively fine lymph-canals lie in the wall of the alveoli in the interspaces of 

 the capillaries, and there are slight dilatations at the points of crossing 

 (Wydwozoff ). According to Pierret and Renaut every air-cell of the lung of the 

 ox is surrounded by a large lymph-space, such as occurs in the salivary glands. 

 When a large quantity of fluid is injected into the lung it is absorbed with great 

 rapidity, even blood-corpuscles rapidly pass into the lymphatics. [Nothnagel 

 found that, if blood was sucked into the lung of a rabbit, the blood-corpuscles were 

 found within the interstitial connective-tissue of the lung after 3^-5 minutes, 

 from which he concludes that the communications between the cavity of the air- 

 cells and the lymphatics must be very numerous.] 



The superficial lymphatics of the pulmonary pleura communicate with the 

 pleural cavity by means of free openings or stomata (Klein), and the same is true 

 of the lymphatics of the parietal pleura, but these stomata are confined to limited 

 areas over the diaphragmatic pleura. [The lymphatics in the costal pleura occur 

 over the intercostal spaces and not over the ribs (Dybkowski).] The large arteries 

 of the lung are provided with lymphatics which lie between the middle and outer 

 coats (Grancher). 



[The movements of the lung during respiration are most important factors in 

 moving the lymph onwards in the pulmonary lymphatics. The return of the 

 lymph is prevented by the presence of valves.] 



[The Nerves of the lung are derived from the anterior and posterior pulmonary 

 plexuses, and consist of branches from the vagus and sympathetic. They enter 

 the lungs and follow the distribution of the bronchi, several sections of nerve- 



