BACILLUS PYOCTANEUS. 537 



its toxic products. Its pathogenic effects on animals 

 have been carefully studied. It is pathogenic for 

 guinea-pigs and rabbits. Subcutaneous or intra-peri- 

 toneal injections of not too small quantities of a 

 recent culture 1 c.c. or more of a bouillon culture 

 usually cause the death of the animal in from twenty- 

 four to thirty-six hours. Subcutaneous inoculations pro- 

 duce an extensive inflammatory oedema and purulent 

 infiltration of the tissues; a serofibrinous or purulent 

 peritonitis is induced by the introduction of the bacillus 

 into the peritoneal cavity. The bacilli multipy in the 

 body, and may be found in the serous or purulent fluid 

 in the subcutaneous tissues or abdominal cavity as well 

 as in the blood and various organs. When smaller 

 quantities are injected subcutaneously the animal usu- 

 ally recovers, only a local inflammatory reaction being 

 set up (abscess), and it is subsequently immune against 

 a second inoculation with doses which would prove 

 fatal to an unprotected animal. Immunity may also 

 be secured by the injection of a considerable amount 

 of a sterilized culture. It is interesting to note that 

 Bouchard, Charrin, and Guignard have shown that in 

 rabbits which have been inoculated with a culture of 

 the bacillus anthracis a fatal result may be prevented 

 by inoculating the same animal soon after with a pure 

 culture of the bacillus pyocyaneus. Similar results 

 have been obtained by Wood head and Wood by the 

 injection of sterilized cultures of this bacillus, made 

 immediately after injection with the anthrax bacillus. 

 Loew and Emmerich have shown that the enzymes 

 produced in the pyocyaneus cultures are capable of de- 

 stroying many forms of bacteria in the test-tube, and 

 have slight protecting value in the body. 



