Amebse and Suppuration 327 



Potato. — Upon potato the growth occurs in the form of a smeary 

 patch of soiled appearance. 



Milk is coagulated. 



Metabolic Products. — The bacillus usually produces alkalies. 

 Indol and phenol are formed from the peptone of the culture- 

 media. Nitrates are reduced to nitrites, and then partly reduced 

 to ammonia. In most culture-media not containing sugar the 

 bacillus produces a disagreeable odor. 



In culture-media containing either grape- or cane-sugar fermenta- 

 tion occurs both in the presence and in the absence of oxygen. 

 Milk-sugar is not decomposed. 



Pathogenesis. — It is a question whether or not Bacillus proteus 

 is to be ranked among the pathogenic bacteria. Small doses are 

 harmless for the laboratory animals; large doses produce abscesses. 

 A toxic substance resulting from the metabolism of the organism 

 seems to be the cause of death when considerable quantities of a cul- 

 ture are injected into the peritoneal cavity or blood-vessels. The 

 bacilli do not seem able to multiply in the healthy animal body, but 

 can do so when previous disease or injury of its tissues has taken 

 place. 



The proteus has been secured in cultures from wound and puerperal 

 infections, purulent peritonitis, endometritis, and pleurisy. When 

 the local lesion is limited, as in endometritis, the danger of toxemia 

 is slight; but when widespread, as the peritoneum, it may prove 

 serious. Bacillus proteus has also been found in acute infectious 

 jaundice and in acute febrile icterus, or Weil's disease. 



Bordoni-Uffredizzi has shown that the proteus quite regularly 

 invades the tissues after death, though it appears unable to main- 

 tain an independent existence in the tissues during life, and is 

 probably of importance only when present in association with other 

 bacteria. It at times grows abundantly in the urine, and may pro- 

 duce primary inflammation of the bladder. The inflammatory 

 process may also extend from the bladder to the kidney, and so 

 prove quite serious. 



Epidemics of meat-poisoning have been thought to depend upon 

 Bacillus proteus. One of them was studied by Wesenberg,* who 

 cultivated the organism from the putrid meat by which 63 persons 

 were made ill. Silverschmidtf and PfuhlJ have made similar in- 

 vestigations with similar results. 



Ameb^ and Suppuration 



The process of suppuration is not confined to bacterial micro- 

 organisms, but is shared to a limited extent by the protozoa. Thus, 



* "Zeitschrift fiir Hygiene," etc., 1898, xxviii. 

 t Ibid., 1899, XXX. 

 t Ibid., 1900, xxxv. 



