Pleitro-Pmiimonia amoiif/st Cattle. 
351 
tissue, which seemed rather to be infiltrated with fluid than 
hepatized by innammation. 
The right lung was apparently healthy, the pleura was not only 
free from exudations^ but exhibited no traces of thickening or 
opacity; but in the middle of the anterior lobe there was a mor- 
bid product, similar to that we had met with in the other lung: it 
was about the size of a split walnut, and was immediately sur- 
rounded by healthy lung, even the pleura covering its surface was 
so transparent, that vessels could he seen ramifying in the tissue 
that separated it from the pleura. We stated before that the 
right lung was apparently healthy, nevertheless a number of air- 
bubbles might be observed beneath the pleura, fig. 5 (b), and 
I'iiJ. 5, Fig. 6. 
Portion of emphysematous Lung. 
Pulmonary tissue, slightly injected. 
Pleural surface, showing empliysematous 
bubbles beneath. 
Interlobular spaces enlarged by emphysema. 
Portion of healthy Lung. 
a; Pleura. 
1>. Pulmonary tissue. 
c. Interlobular spaces. 
also in the inter-lobular cellular tissue (c). The parenchyma of 
the whole lung represented the appearance designated " vesicular 
emphysema," a state in all probability due to the increased func- 
tional work it had to perform, in consequence of the general im- 
permeability of the left lung to air. In order to convey better 
an idea of the changes which the lungs undergo in this disease, 
we have thought proper to add a drawing of a portion of the 
healthy lung of a bullock, see fig. 6; (a) represents the serous 
or pleural, (b) the incised surface, (c) the interlobular spaces. 
In the descriptions just given, allusion to the state of the mucous 
membrane of the bronchial tubes is only made in fig, 3, and in 
