Fig. 27. a. Azotobacter chroococcum, Wilson E-7. Peritrichous flagella 

 with normal curvature. These organisms are from a suspension to which 

 K^HPO^ had been added prior to the formalin. The average normal wave- 

 length of this strain was 2.70 microns. 



b. A. chroococcum, Wilson E-7. Peritrichous flagella with curly curvature. 

 These organisms are from a suspension to which KH-.PO^ had been added 

 prior to the formalin. The average curly wavelength was 1.20 microns. 



c. A. vinelandii, Wilson O. Peritrichous flagella of normal curvature. Aver- 

 age normal wavelength was 2.71 microns. 



d. A. agilis, Wilson 4-4. Peritrichous flagella typical in this culture with 

 partly normal and partly coiled curvature. Average wavelength about 3.2 

 microns. 



e. A. irulicum, ATCC 9039. Peritrichous flagella of short wavelength com- 

 parable to the curly type of A. chroococcum. Note the polar tendency of the 

 flagella. The average flagellar wavelength was 1.0 micron. 



f. g. A. (Azotomonas) macrocijtogenes, NCIB 8700. Polar multitrichous 

 and polar monotrichous flagella. The soma of this organism is much like that of 

 the typical Azotobacter strains but the flagella are distinctly different both as 

 to arrangement and shape. Average wavelength was 1.7 microns. 



64 



