62. Appendix 



Mlxed Flagellation 



Cultures of bacteria in which are constantly found individuals 

 with both polar and lateral flagella are not common. A typical 

 example was illustrated in Chromobacterium. Another example is 

 that of an unidentified organism from water illustrated in Figs. 

 69a to 69f inclusive. In this mixed type of flagellation the polar 

 flagella have invariably shown a greater wavelength than the 

 lateral flagella. If the wavelengths were the same the phenomenon 

 would probably be overlooked and the organisms regarded as of 

 the ordinary peritrichous type. 



Filaments of Polar Flagellates 



Filamentous mutants of polar flagellated bacteria may have the 

 appearance of peritrichous flagellation. If the cellular units in the 

 filament are long and the organism is polar multitrichous or lopho- 

 trichous, the true nature of the flagellation is usually obvious. Tufts 

 of lateral flagella at regular intervals is not characteristic of peri- 

 trichous flagellation. An example of this type is shown in Fig. 

 69g. Other examples are the Fseudomonas sp. illustrated in Fig. 

 9s and the Lophomoiias illustrated in Fig. 16c. If the cellular units 

 in the filaments are very short the true nature of the flagellation 

 may be difficult to recognize. 



Filaments of polar monotrichous organisms may be very diffi- 

 cult to recognize for what they are. In Figs. 69h and 691 are il- 

 lustrated the nonfilamentous and filamentous form of an unidenti- 

 fied, nitrogen-fixing, soil organism. This organism was originally 

 described in the literature as peritrichous or showing mixed flagel- 

 lation with a polar flagellum which appeared to be thicker than 

 the lateral flagella. This culture was obtained and, on plating, both 

 rough and smooth colonies were found. The smooth colonies were 

 composed of polar monotrichous short rods, illustrated in Fig. 69h. 

 The rough colonies were composed of long and short filaments 

 with flagella which had the appearance of being peritrichous. A 

 short filament is illustrated in Fig. 69i. In pure form this fila- 

 mentous mutant might be difficult to recognize for what it is. 



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