BUREAU OP ANIMAL INDUSTRY. 623 



case did a bacterium resembling the microlje of hog-cliolora appear 

 amongst a mimbei of other forms. We shall return to this case later on. 



Of the slide preparations tlie dried films were searched in vain for 

 the presence of the bacteria, indicating plainly the external origin of 

 the putrefactive forms. Plate cultures were made in a few cases 

 without any promising results. Mice were inoculated with bits from 

 a number of the spleens by introducing them beneath the skin of the 

 back. A few mice died, prol)ably of malignant cedema, and the rest 

 remained well. 



In only one case was the result unexpectedly^ successful. This 

 came from Tecumseh, Nebr., the spleen in which the bacterium 

 seemed present in cover-glass preparations. Plate cultures and line 

 cultures directly from spleen pulp were equally unsatisfactory, owing 

 to the variety of germs present. 



Two mice, Nos. 69 and 70, inoculated with bits of spleen tissue, fm-nished a key- 

 to the problem. Both were inoculated March 23; one died March 30, the other 

 April 1. In No. 69 there was a very large quantity of serum in the subcutaneous 

 tissue of the skin about the abdomen and in the abdominal cavity. The liver, es- 

 pecially along its border, was dotted with small patches of coagulation necrosis, A 

 cover-glnss pre]>aration of spleen and liver negative. The culture from the effusion 

 contained stn-eral forms of bacteria, as might have been expected. A liquid culture 

 of the blood seemed a pure culture of a motile oval haderiam, resembling closely 

 the bacterium of hog-cholera. In No. 70 the lesions were more nearly identical 

 with those observed after inoculating mice with the bacterium found in the East. 

 The lymphatics of the knee fold and the spleen were very much enlarged; the 

 liver contauied small patches of coagulation necrosis; lungs and kidneys congested. 

 Bacteria, not to be distinguished from those of hog-cholera, were found abundantly 

 in spleen, Uver, and heart's blood; m small number in lungs and kidney. The liquid 

 cultiu-e was identical with tliat from No. 69. A tube culture in gelatine and line 

 cultures from the liquid cultures failed to gi'ow for reasons discovered later on. 



In order to determine whether the bacterium obtained from these mice was patho- 

 genic or not, foiir mice were inoculated April 6 (Nos. 75 and 76), from the culture 

 of No. 69, 77, and 78 from the culture of mouse 70, each receiving from 5 to 10 

 drops of the culture hquid. April 12 all four mice were found dead. In No. 76 

 there were signs of commencing necrosis in the liver. There were no marked 

 lesions observed excepting a variable enlargement of the glands in the knee fold. 

 In the liver and spleen of every animal the oval bacteria, ^^^th pale center, were 

 present in large numbers. As these had succumbed in less than six days, the most 

 characteristic lesions, great enlargement of the spleen and coagulation necrosis in 

 the liver, were absent. These changes were invariably produced with the hog- 

 cholera bacterium first described when very minute quantities were inoculated, by 

 which the period of disease was prolonged for nearly two weeks from the date of 

 inoculation. April 20. Nos. 84 and 85 were inoculated with 5 drops of a culture 

 derived from mouse No. 78. No. 84 died in two days, and No. So died in six after 

 inoculation. In both the charat'.teristic bacteria were present in spleen and liver. 

 At the same time Nos. 82 and 8;3 were inoculated from the culture obtained from 

 the blood of mouse No. 77. No. 82 died two days after, and No. 83 seven days 

 after, inoculation. In the latter case the longer time had allowed the formation of 

 coagulation necrosis in liver and great enlargement of the spleen. 



This new microbe, identical morphologically with the bacterium 

 of hog-cholera already described, produces a disease in mice which 

 is practically the same as that produced by the latter microbe. 



The effect of these two bacteria is the same on rabbits. May 22 a 

 young rabbit received subcutaneously an equivalent of .001*=° of the 

 eleventh culture (mouse) four days old. No symptoms of disease aj)- 

 peared until June 5, fourteen days after inoculation. It was tlien 

 very quiet, refusing to move and breathing with some effort. On the 

 f oUoAving day it was found dead. The autopsy revealed the following 

 lesions: 



At the place of inoculation was found a yellowish- white mass resting on thg 

 muscular tissue and covering an area about 2"='™ in diameter. This mass, consistine 



