Report on the Pathological Anatomy of Pleuro-pneumonia. 171 
part affected by the disease, which generally begins under the 
pleura but also occasionally in the deeper interlobular tissue. 
He distinguishes two forms of this interlobular pneumonia. 
One wide-spread and diffuse, extending over an entire lung. 
The other, which attacks a small, sharply bounded part of the 
lung, like lobular pneumonia. These occur with equal fre- 
quency, and he expressly states that their difference merely 
depends on extent and anatomical arrangement, their mode of 
origin being identical. 
Klebs* describes one case in which he found good examples 
of vascular plugging. He thinks the disease resembles in most 
respects ordinary pneumonia, but can be distinguished by the 
coagulation in the vessels. 
Rollf considers that this disease corresponds with the inter- 
stitial pneumonia of other animals. The first steps, he thinks, 
occur in the connective tissue between the lobules, most com- 
monly in the deeper parts of the lung. This tissue becomes 
congested, and a serous exudation takes place into it, which 
greatly swells the interlobular spaces. The congested pul- 
monary parenchyma is thus pressed upon, and ultimately 
becomes quite airless. The serous fluid more rarely fills the 
air-cells themselves, and still more unusual is the occurrence 
in them of the firm exudation of ordinary inflammation. He 
describes the various secondary lesions which may arise in the 
course of the disease, and amongst them he mentions bronchial 
and pleural inflammation. 
Bruckmiiller J considers the pleuro-pneumonia of cattle to 
correspond exactly with ordinary pneumonia of other animals, 
the peculiar construction of the lung sufficiently accounting for 
the peculiarities in the pathological anatomy of the pneumonia 
of bovine animals. 
" There is only one form," he says, " of inflammation of the 
lung in cows, and this is always associated with very striking 
changes in the interstitial tissue." He describes the disease under 
the title " croupous interstitial inflammation of the lung," and 
he says, " If we compare the pathological products which arise 
in the lungs of cows affected with pleuro-pneumonia {Lungen- 
seuche) with the products of inflammation of the lungs in other 
animals, we can find no real difference." He denies its specific 
nature and its contagiousness, but says it is a good example of 
an infectious complaint. 
The scientific pathology of this disease has not been studied 
in England with great care or success. The morbid appearances 
* Virchow's Archiv., Bd. xxxviii. p. 326. 
t Lehrbucli d. Pathologic u. Theiapie d. Ilausthiere. Wien, 1860. 
X Lekrbuch d. Path. Zootomie. Wien, 1862. 
