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J. T. DUNCAN 
broncho-vascular system, and forms the bed of large lymph chan¬ 
nels. 
5th. The lymph from the interlobular spaces passes along the 
peri-broncliial passages. 
6th. As the lymph vessels follow the course of the broncho- 
vascular systems, those around any given system must drain the 
territory of the lung tissue supplied by that system. 
7th. The subpleural lymphatics seem to take a less important 
share in draining the tissue than is the case in many other ani¬ 
mals. 
In order that we may more clearly understand the changes, 
we notice, first, the Pleural; second, the Lung , and third, the 
Broncho- Vascular lesions. 
Changes in the Pleura .—These show pleurisy of an acute 
type, differing, however, in not being diffused, as in ordinary 
pleurisy, but localized. Wherever the lung below is the seat of 
disease, the pleura above is covered with a dense fibrinous exuda¬ 
tion. As the disease advances in the substance of the lungs, the 
contiguous lobes become firmly cemented by the adhesion of their 
pleural surfaces. The visceral and parietal surfaces are generally 
separated by a quantity of fluid effusion, which is thin,yellowish or 
greenish in color, coagulating after removal, showing the presence 
of some fibrin. If the anterior lobes are affected, the pericardium 
generally becomes inflamed and thickened as well as the pleura. 
To sum up: 
1st. It has the character common to the ordinary forms of 
acute pleurisy. 
2nd. It always varies in degree of severity in different parts 
of the same pleura. 
3rd. Its point of greatest intensity corresponds to the appa¬ 
rent starting point of the lung lesion. 
4th. It is not an invariable or essential part of the disease, for 
the lung may show disease and the pleura not. 
5th. It usually appears to be of more acute type and more re¬ 
cent development than the lung lesion. 
6th. Its occurrence often gives the first indication of the ex¬ 
istence of disease. 
