MORBID ANATOMY 5II 



times present. The mucous membrane of the larynx and 

 bronchi is hyperemic, swollen, often infiltrated with hemor- 

 rhages and covered with pus. Sometimes catarrhal ulcers 

 appear. The large bronchial tubes often fail to exhibit 

 changes which might have been expected from the symptoms. 

 The smaller bronchi are on the other hand frequently filled 

 with a dirty gray and even bloody, viscid pus. There are 

 areas of congestion on the surface of the lungs, some parts of 

 which may contain but little air. There may be areas of col- 

 lapse or those abnormally filled with air. The inflammatory 

 foci of the lungs are usually consolidated. In very young 

 animals there may be a fibrinous exudate which is very soft 

 and which readily liquefies. The hepatization frequently 

 involves an entire lobe. The hepatized parts are frequently 

 studded with small suppurating foci, or are diffusely infiltrated 

 with pus. The pleura over the affected parts is often inflamed. 

 The bronchial glands are swollen or infiltrated with a serous 

 fluid or with pus. 



In the digestive system, the mucous membrane of the 

 stomach and intestines, especially that of the small intestine, 

 is hyperemic and swollen. It may be covered with a tough 

 mucus and is often sprinkled with hemorrhages. In other cases 

 it is very pale, swollen and easily torn. Frequently the con- 

 tents of the intestine are blood stained and the mesenteric 

 glands enlarged and edematous. 



The brain is anemic and often there is a .serous effusion 

 into the lateral ventricles and subarachnoid spaces. In a few 

 cases there are signs of a purely venous, cerebral hyperemia, 

 as for instance, great congestion of all the sinuses, venous 

 plexuses and vessels of the pia and the appearance on the cut 

 surfaces of the brain of numerous blood points which can easily 

 be wiped off. Kolesnikoff found microscopically the brain 

 substance, especially the walls of tlie vessels, infiltrated with 

 leucocytes. Krajewski noticed dilation of the vessels, cellular 

 infiltration of their walls, filling of the perivascular spaces 

 with lymphoid cells and migration of lymphoid cells into the 

 stroma of the brain and into the protoplasm of the ganglionic 



