364 APPLICATION OF METHODS OF BACTERIOLOGY 



Note. — To a fresh agar culture of this organism, in 

 which the green coloration of the medium is especially 

 marked, add about 2 c.c. of chloroform. Shake gently, and 

 note that the chloroform extracts a blue coloring-matter 

 from the culture, leaving the latter more or less yellow. 



Fig. 70 



Fig. 71 



Fig. 72 



J:'flf:», 





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Fig. 70. — Stab-culture of ps. mruginosa in gelatin after twenty-eight 

 hours at 22° C. 



Fig. 71. — Colony of ps ceruginosa after twenty-four hours on gelatin at 

 20°-22° C. 



Fig. 72. — Colony of ps. ceruginosa after forty-two hours on gelatin at 

 20° -22° C. 



Allow the chloroform extract to stand for several days; 

 note what occurs; how do you account for it? 



Prepare a 100 c.c. Ehrlenmeyer flask with 75 c.c. of 

 sterile bouillon or peptone solution. Inoculate it with this 



