PLATE 4 



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

 showing large irregular amoeboid cells, varying in density of protoplasm, also 

 some granular forms; stained with He'denhain's iron hematoxylin. X 1000. 



Fig. 2. Azo. 2. Smear from culture on Ashby's agar two days old at 37°C, 

 showing darkly stained granules within the cells; stained Neisser's blue. X 

 1000. 



Fig. 3. Azo. 3. Smear from culture on Ashby's agar two days old at 37°C, 

 showing large granular cells apparently budding. Stained Neisser's blue. X 

 1000. 



Fig. 4. Azo. 1. Large motile cells that were observed to break away from edge 

 of colony four days old growing on agar hanging block in warm stage moist cham- 

 ber, and swim around for twenty minutes or so in water of condensation accumu- 

 lated at edge of colony. Photographed in living condition when quiescent. X 

 1000. 



Fig. 5. Azo. 3. Smear from culture seven days old on Ashby's agar at 25° C, 

 showing large granular cells and some involution forms with many small granules, 

 positive to stain. Stained Neisser's blue. X 1000. 



Fig. 6. Azo. 1. Smear from culture seven days old at 37°C. on Ashby's agar 

 showing various elongated involution forms, some granular and some with homo- 

 geneous protoplasm. Stained with Neisser's blue. X 1000. 



340 



