186 Report on the Pathological Anatomy of Phuro-pneumonia. 
amidst the dense, fibrous tissue in which they lie. The small 
bronchi are all plugged in this condition, while in the trans- 
lucent form they are all free and pervious. 
This kind of indurated tissue is always pale and bloodless. 
The pulmonary vessels are usually closed by pressure, but the 
nutrition of the part seems amply provided for by the bronchial 
vessels, which are more obvious than they become in the later 
stages. In many parts thus indurated, the lobular tissue may 
retain a certain amount of vascularity, its colour then con- 
trasting most strikingly with the thick interlobular spaces, 
which are white and glistening. 
This fibroid change reminds one of the condition of the 
human lung in the very advanced stage of interstitial-pneumonia 
which has been called cirrhosis. It differs, however, from that 
in a very essential point, namely that there appears no tendency 
to contraction of the fibroid tissue, such as is found in cirrhosis, 
causing shrinking of the lung and dilatation of the bronchi, «Scc. 
On the other hand, in the fibroid consolidation of pleuro- 
pneumonia, the infected part invariably seems to be increased 
in size. It is certainly possible that, if life continued long 
enough the shrinking might take place, for the contracted state 
known as cirrhosis only occurs as the ultimate result of old 
interstitial pneumonia. 
Microscopic examination of the different stages of this con- 
solidation shows various gradations in the exudation material. 
From being a fibrinous mass packed with cells, it changes to a 
kind of cicatricial tissue. The capillary vessels are frequently 
found to be filled with blood corpuscles. The bronchioles and air 
vesicles contain masses of different kinds of cells, some small, 
round, and pale, but the majority large, and coarsely granular. 
In a few cases, peculiar small bodies were found in the cavity 
of the air vesicles. In certain parts they were so numerous that 
two or three came into the same field of the low power (Hart- 
nack, Obj. No. 4). They were most strikingly regular in size, 
measuring about of an inch in diameter. Their shape 
was nearly spherical, or very slightly oval. In structure they 
appeared to be made up of small rods very closely set together, 
and radiating from the centre of the body. They resisted the 
action of the strongest reagents, even such as completely de- 
stroyed every trace of the lung tissue ; in fact everything seemed 
to make them darker and more distinct. They are like crystals 
of tyrosin, but they do not respond to the tests for that substance. 
The exact nature of these bodies I have not been able to 
determine, but, from the rarity of their occurrence, I have come 
to the conclusion that they cannot be said to have any important 
bearing on the pathology of the disease. 
