PLATE 2 



Fig. 1. Azo. 1. Smear from culture one month old in Ashby's solution, showing 

 to the left two mother cells disintegrating, the liberated reproductive granules 

 developing into short rods before dispersal. Stained with Heidenhain's iron 

 hematoxylin. X 1000. 



Fig. 2. Azo. 1. Smear from culture fourteen days old on Ashby's agar at 25°C., 

 showing granular mother cells disintegrating. Stained with saturated alcoholic 

 gentian violet which stains the capsule material, forming the background, leaving 

 the organisms mostly negative to the stain. X 1000. 



Fig. 3. Azo. 2. Similar preparation to figure 1 from culture of Azo 2 of same 

 age. X 1000. 



Fig. 4. Azo. 4. Smear preparation from a culture in Ashby's solution one 

 month old at 25°C, showing various cell forms, particularly dispersed reproduc- 

 tive granules in various stages of development into young cells multiplying by 

 fission. Stained with Heidenhain's iron hematoxylin. X 1000. 



Fig. 5. Azo. 4. Similar preparation to figure 4 from culture one month old in 

 Ashby's solution showing young rods and spheres developing from liberated repro- 

 ductive granules, also small clusters of resting cells. 



Fig. 6. Azo. 3. Smear from a twenty-hour old streak culture on Ashby's agar. 

 Most of the cells shown are very young ones developing from dispersed reproduc- 

 tive granules and multiplying by fission. Stained with Neisser's blue. X 1000. 



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