^28 MANUAL OF BACTERIOLOGY. 



Spirillum sputigenum. Found in the human mouth in 

 healthy persons at the margin of the gums; curved rods or 

 short spirals which resemble the spirillum of cholera in 

 form ; has not been cultivated. 



Spirillum rugula (Vibrio rugula). Found in swamp 

 water, in fecal matter, and in the tartar of the teeth ; a 

 curved rod .5 to 2.5^ broad and 6 to 8/2 long, having one 

 flat spiral winding; motile, with flagella at the ends; prob- 

 ably anaerobic; forms spores located at the ends. 



FIG. 50. 



- 



^ X 



. <\ 



Spirilla from Swamp Water. (X about 500.) 



Spirillum volutans. Found in swamp water; very long 

 spirals with several turns; 1.5 to 2 /* broad and 25 to 30 // 

 long; motile, with a flagellum at each extremity. The 

 protoplasm is granular. 



Spirillum undula. Found in putrefying infusions con- 

 taining organic matter ; a rather short spiral form with three 

 turns or less, about i [* thick and 8 to 12^ long; actively 

 motile, with a tuft of flagella at each extremity; has been 

 cultivated on agar. 



