GENUS BACTERIUM 271 



polar stain in preparations from tissues and in cultures they 

 may appear in short chains. The marked polar stain often 

 suggests a diplococcus. They state that it is destroyed at 

 58 C. in 8 minutes and by a 1-5000 solution of mercuric 

 chloride in one minute. The method by which this organism is 

 disseminated is not. known. The disease it produces appears 

 at all seasons of the year. The specific bacteria are often 

 found in smears made from the hemorrhagic foci and from 

 the various organs and blood. It is pathogenic for the bovine 

 species and by inoculation for rabbits and guinea-pigs. It 

 seems to lose its virulence for cattle after it has been culti- 

 vated artificially for a few generations. 



BACTERIUM SUISEPTICUM (KRUSE) MIGULA. 



Synonyms. Bacillus of Schweineseuche Loeffler and 

 Schiitz 1 ; Bacillus of swine plague Smith 2 ; Bacillus suisepti- 

 cus Kruse 3 ; Bacterium suicida Migula. 4 



Place in nature. Bacterium suisepticum is the cause of 

 the disease in swine known as swine plague, or infectious 

 pneumonia. This organism is found in the lungs, often in 

 other organs of pigs suffering from this disease. An organism 

 that can not be differentiated from it is found in the mucus 

 of the larynx in about -50 per cent of healthy pigs. This or- 

 ganism was first discovered by Loeffler and Schiitz in 1885 as 

 the cause of Schweineseuche. In 1886 Theobald Smith iso- 

 lated it from cases of swine plague. It is not known to exist 

 in nature outside of the infected animal and in the upper air 

 passages of a certain percentage of healthy swine unless it is 

 proved to be identical with the forms in the upper air passages 

 of other animals. 



Morphology. A rod-shaped organism varying from 0.8 

 to 2 /x in length and from 0.4 to 1.2 /x in breadth. The ends 



1 Loeffler and Schiitz. Arbeit aus dem Kais. Gesundheitsamt, 

 Bd. I (1886) p. 376. 



2 Smith. Special Report on swine plague, B. A. I., Washington, 

 D. C., 1893. 



3 Kruse. loc. cit. * Migula. loc. cit. 



