730 



THE EESPIEATOEY TRACT. 



The examination of the sputa with the microscope throws light upon a 

 number of morbid processes in the respiratory tract. I have previously pub- 

 lished some of the results of my researches concerning the examination of 

 sputa.* 



The corpuscular elements found in the discharges of the respiratory passages 

 are the following: Flat epithelia of the oral cavity ; columnar epithelia from the 

 larynx, the trachea, the bronchi, and bronchioli; these are rarely seen ciliated, 

 since the cilia break off easily. Flat epithelia of the alveoli of the lungs, which 

 slightly surpass in diameter those of the kidneys, and, as a rule, are found 

 swelled and globular. In smokers, or persons exposed to smoke, they contain 

 a varying amount of pigment (charcoal) granules. In addition, sail ran/, 

 mucus- &nd.p us-corpuscles are found, besides a granular detritus, entangled with 

 mucous threads evidently arising from the bursting or disintegration of the 

 above-named corpuscles. Leptothrix, micrococci, and bacteria are also common 

 occurrences in the sputa of even simple catarrhal inflammation. Lastly, the 

 remnants of animal and vegetable food are found. 





FIG. 328. SYPHILITIC PNEUMONIA. 



J, interstitial tissue, crowded with inflammatory corpuscles ; F, alveolus containing de- 

 tached epithelia and coagulated fiurine; M, alveolus tilled with a granular mass holding 

 nuclei. Magnified 600 diameters. 



'" The most common question of physicians is: What is the difference 

 between mucus and pus-corpuscles? The mucus, as well as the salivary 

 corpuscles, are plastids, formerly inclosed in a shell of cement- substance, and 

 thus forming what we call epithelia. The transformation of the contents of 

 epithelia into saliva, mucus, and pepsin, has been carefully studied by K. 

 Heidenhain. The transformation into mucus can be demonstrated directly 

 on the epithelia of mucous glands of the frog's skin, and on the columnar 

 epithelia of the small intestine of any freshly killed animal, from which we 

 remove parts of the mucous lining with curved scissors. On the epithelia of 

 such slices we succeed in watching the process of the formation of mucus- 



* " The Aid which Medical Diagnosis Keceives from Recent Discoveries in Microscopy." 

 -Archives of Medicine, Feb., 1879. 



