common monotrichoiis types have a predominantly single flagellum 

 at one or both poles, rarely two flagella at one pole. The flagellar 

 wavelength (Table I) is remarkably uniform averaging from 1.7 

 to 1.8 microns. The common multitrichous types usually have from 

 two to five flagella at one pole, less often at both poles. The wave- 

 length of these flagella is distinctly greater than that of the mono- 

 trichous types, averaging from 2 to 2.5 microns. Flagella of longer 

 wavelengths are rare and usually limited to strains of the plant 

 pathogens. The extremes of wavelengths are illustrated by P. 

 diminuta, wavelength 0.7 micron, and Fseudomonas nigrifaciens. 



Fig. 9. s. Pseudomonas sp., Fulton 3984. Culture isolated from human 

 pleural fluid at autopsy. Typical polar multitrichous flagellation. The chain of 

 bacilli show where and when the new flagella develop on the daughter cells. 

 In this organism the new flagella develop only after cell division is complete 

 and on the distal pole. 



t. Pseudomonas sp. Organism isolated from the water of the DuPage 

 River. Capsulated organisms of this type are not infrequent in water. 



u. Pseudomonas sp. The organism pictured is an example of mixed flagella- 

 tion. Note the difl^erence in wavelength of the polar and the lateral flagella. 

 The organism was isolated from a live oyster. 



Fig. 10. The phytopathogenic pseudomonads. 



a. Pseudomonas angulata, Starr PA 12. Polar multitrichous or lophotrichous 

 flagella. 



b. P. cattleyae, Starr PC 107. Polar multitrichous flagella. 



c. P.savastanoi, Starr PS 111. Polar lophotrichous flagella. 



d. P. glycinea, NCIB 8613. Polar lophotrichous flagella. 



e. f. P. washingtoniae, Starr PW 2. Polar multitrichous flagellation. In e 

 the two upper flagella have distinctly different wavelengths, the shorter meas- 

 uring 2.02 microns and the longer 2.57 microns. Many individuals in this 

 culture were mototrichous as illustrated in f. 



g. Pseudomonas sp., Starr YCLS. Polar multitrichous flagella. This organ- 

 ism was reported by Dr. Starr to be pectolytic. It was physiologically typical 

 of the genus, and produced a reddish-purple water soluble pigment. 



h. P. marginata, Starr PM 15. Polar multitrichous flagella. The soma is 

 stained rather lightly. 



i. P. rihis, Starr PR 5. Polar multitrichous flagella of imusually long wave- 

 length. Coiled flagella were frequent. 



j. Pseudomonas sp.. Smith Cabbage 2B. Polar lophotrichous flagella. This 

 organism was isolated by M. A. Smith, U.S.D.A., from diseased cabbage. 



k. P. savastanoi var. fraxini, Starr PS 19. Polar lophotrichous flagellation. 

 The flagella are short with a tendency to coil. 



1. P. polycolor, Starr PP 2. Polar monotrichous flagella. The phytopatho- 

 genicity of this organism seems doubtful. Morphologically it is not typical of 

 the phytopathogenic pseudomonads. 



28 



