292 
V. A. MOORE AND F. L. KILBORNE. 
invariably enlarged and reddened, due to hyperasmia. They 
contained a very large amount of pigment, which appeared in 
granules from 0.8 to 2.0 in diameter. It resembled in form 
the grains of gunpowder. The pigment was usually observed 
lying between the cells. In most cases the liver cells were 
more or less fatty. In stained sections {rabbits Nos. 476 and 
15) the pigment showed as bluish particles, the capillaries 
were distended with blood. The cell nuclei and interlobular 
tissue were not appreciably changed. The spleens were nor¬ 
mal in size and color. The kidneys were hyperasmic, and in 
most instances the tubular epithelium was granular. In 
stained sections (from rabbits Nos. 476 and 15) parenchyma¬ 
tous degeneration was more or less marked. The blood ves¬ 
sels were usually injected. There was no apparent thicken¬ 
ing of the intertubular tissue. The bladder contained very 
little or no urine. The stomachs, as a rule, contained little 
food. There was no visible intestinal lesions. The lymphat¬ 
ics were apparently normal. 
Bacteriological Examination .—The specific bacteria were 
demonstrated, as previously stated, in the pleural and peri¬ 
toneal exudates, but never in cover-glass preparations from 
the various organs and blood. Cultures were made from 
nearly every animal that was in a suitable condition, and in 
every case those from the blood remained sterile, and in only 
two out of eleven cultures from the livers did the rabbit sep¬ 
ticaemia bacteria develop. The bacteria were loca'ized on 
the serous membranes, more especially the pleura. The 
cause of the lung infection will be apparent from the fact, 
which will be further discussed, that the bacteria presuma¬ 
bly gained entrance to the pleural cavity through the bron¬ 
chioles and air-cells. The power of the attenuated forms of 
the swine-plague group of bacteria to multiply on the serous 
membranes of rabbits has elsewhere* been brought out by 
one of us (V. A. M.), but in no other investigations or experi¬ 
ments have we found such a marked example of this property 
of bacteria as in this outbreak. 
* Appendix. Special report on the cause and prevention of swine-plague, 
Department of Agriculture, 1891. 
