PLATE X. 



FIG. i. Sarcina lutea. 



Growth on sterilised potato five days after inoculation 

 from a tube-cultivation. Potatoes, especially old 

 ones, have sometimes a tendency to become dis- 

 coloured, and the brown appearance in this figure has 

 nothing to do with the growth of the organisms. 



FIG. 2. Saccharomyces rosaceus. 



Pink torula. 



Growth on sterilised potato which had been inoculated 

 from a colony contaminating a plate-cultivation. 

 This yeast develops a coral-pink colour, but does 

 not grow so luxuriantly as the chromogenic bacteria. 



