318 MANUAL OF BACTERIOLOGY. 



the growth is usually brown; the surrounding medium may 

 be tinged with green. Milk is coagulated and peptonized 

 and an acid reaction is developed. Indol is formed in Dun- 

 ham's peptone solution. Coagulated blood-serum is liquefied. 

 The Bacillus pyocyaneus seems to be rather widely dis- 

 tributed in nature; it has been found on the skin, in normal 

 feces, also in diarrheal discharges and in dysentery. It is the 



* V s * * - K> 



' 1 < "a U >* ; 



FIG. 75. Bacillus pyocyaneus pure culture. (X 1000.) 



cause of the color in blue or green pus. It has frequently been 

 demonstrated in pus, but oftenest perhaps, in mixed infections. 

 It has been found in various abscesses, in otitis media, peritoni- 

 tis, appendicitis and bronchopneumonia. It has been known 

 to produce general septicemia.* It is pathogenic for guinea- 

 pigs and rabbits, in whom it may produce septicemia. In 

 animals it may lead only to local suppuration, from which they 



*Lartigau. Philadelphia Medical Journal. September 17, 1898. Journal 

 Experimental Medicine. Vol. III. 1898. Perkins. Journal of Medical Re- 

 search. Vol. VI. 1901. 



