54. Rhodospirillum 



Two species of Rhodospirillum are listed in Bergey's Manual, 

 Rhodospirillum rubrum and Rhodospirillum fulvum. Several strains 

 of R. rubrum were obtained for study from several sources. R. 

 fulvum was not obtained. 



Flagellar Characteristics 



R. rubrujn is a typical spirillum with a tuft of polar flagella at 

 one or both ends. The flagella rarely have more than one curve 

 as in most spirilla (Fig. 61). 



5 5. Nocardia 



The great majority of Nocardia organisms encountered in na- 

 ture appear to be nonmotile and presumably nonflagellated. A cul- 

 ture labeled Nocardia, Orskov, was received from Mortimer P. 

 Starr of the University of Cahfornia (Fig. 62). This strain origi- 

 nated from Dr. J. Orskov in Denmark. The culture showed mainly 

 relatively small pleomorphic rods with a few short filaments. Mo- 

 tility was fair. 



Flagellar Characteristics 



The majority of individuals showed only one flagellum or none. 

 A fair number showed two flagella and a few showed many flagella. 

 The flagella were very irregular as to length and curvature. Some 

 were almost straight, others coiled, and some showed uneven 

 waves. The arrangement of the flagella was distinctly nonpolar or 

 peritrichous. The wavelength of the wavy flagella was very great 

 but so uneven that an average wavelength has little significance. 

 The most distinct waves measured around 5 microns in length. 



146 



