44 . DISEASES OF SWINE AND OTHER ANIMALS. 



bolisiii. Tlie other morl)i(l cliaiig'es, usually found in the thoracic cavity, 

 such as ])leuriti.s, peiicarditLs, accumulation of straw-colored scnmi, and 

 the morbid clianges found sometimes in the heart, but especially in the 

 auricles, in "which, in numerous cases, the capillary vessels have been 

 found to be gorged with blood, tend also to show that embolism consti- 

 tutes the cause, or at least the main cause, of all those changes. The 

 microscope very fortunately has revealed how this embolism is effected. 

 The cai^illaries of the lungs, as is well known, are narrower than those 

 in other parts of the body. The blood of the diseased animals, and es- 

 jiecially the blood-serum deposited in the affected pulmonal tissue, con- 

 tain invariably large numbers of bacillus-germs and hnclUl. These bacil- 

 lus-germs, as I have observed with the microscope, and as Hallier, who 

 calls them micrococci, nine years ago found, bud and develop to hacilli, 

 and show, at a certain period of their development, a great tendency to 

 agglutinate to each other, and to form in that way larger or smaller, ir- 

 regular-shaped, and apparently somewhat viscous clusters. (See draw- 

 ing II, fig. 1 ; drawing- IX, fig. la.) These clusters, or some of them, 

 are large enough to close or to obstruct the finer capillaries, and to stop 

 in that way the capillary circulation. As a necessary consequence, the 

 serum of the blood transudes through the walls of the capillary vessels, 

 and is deposited in the tissue of the lungs, in the thoracic cavity, and in 

 the ijericardium. In some cases, and at some places, the tender walls of 

 the finer capillaries yield to the ]U'essure and rupture, and then extrava- 

 sations of blood, such as have been observed in several cases, are the con- 

 sequence. The capiUary redness, and the red and i)urple spots observed 

 in certain comparatively fine portions of the sldn, and in the subcu- 

 taneous tissues, I have no doubt, are also a product of the same process, 

 and are caused by capillary embolism. If the animals would only live 

 long enough, gangrene or mortification of parts of the skin would be met 

 with quite often, but as other morbid changes cause death, and thus 

 terminate the morbid process usually before the stagnation of the blood 

 in the skin becomes perfect, gangrene or mortification has been found 

 only once in the skin on the lower surfiice of the body. Certain morbid 

 changes in the abdominal cavity, such as abdominal dropsy, and the 

 blood extravasations found repeatedly in various organs, such as stom- 

 ach and intestines, are due to the same cause. The clusters of bacillus- 

 germs also constitute probably the causeof the swelling of the l^Tuphatic 

 glands. Microscopic examinations of the interior of those glands (see 

 drawing IV, fig. 3) revealed invariably, besides some lymi^h-corimscles, 

 immense numbers of haciUi and bacillus-germs in different stages of de- 

 velopment, some budding, some agglutinated to each other, and some 

 in process of agglutination, &c. These clusters of bacillus-germs, it 

 seems, not only close the capillary blood-vessels, but probably also the 

 finer lymphatics ramifying in the glands ; a swelling of the latter, there- 

 fore, is a natural consequence. 



The production of the morbid growths (swine-plague tumors would be 

 a good name), which are found in nearly every case on the raucous mem- 

 brane of the ciecum and colon, and sometimes, though not so often, on 

 the mucous membrane of other intestines, such as ilium, jejunum, duode- 

 num, stomach, gall-bladder, and uterus, and even on the conjunctiva and 

 the gums, is not so easily explained. It seems that a proliferous process 

 is taking place; new epithelium-cells and connective-tissue corpuscles 

 are formed rajndly, but decay be lore fully developed. Tliese new morbid 

 and rapidly decaying cells are imbedded in a stroma of a dense connec- 

 tive tissue which, too, is a morbid i)roduct, and formed ra])idly. In the 

 older and larger morbid growths or tumors in the caecum and colon this 



