696 



NON- PATHOGENIC SPIRILLA. 



later tli is acquires a yellowish tiut; the growth penetrates the potato to a 

 considerable depth. Much gas is formed in all of the cultures, and they 

 give off a strong faecal odor. According to Prazmowski, Vibrio rugula 

 causes an energetic decomposition of cellulose. 



415. SPIRILLUM VOLUTANS (Ehrenberg). 



Found in swamp water, etc. 



Morphology. Spiral filaments with round and somewhat pointed ends, 

 from 1.5 to 2 /u thick and 25 to 30 //long; each filament consists of two 

 and one-half to three and one-half rarely six or seven spiral turns which 

 are from 9 to 13 p long; a single long, whip-like flagellum at each extremity ; 

 the protoplasm contains numerous opaque granules. Exhibits active rotary 

 and progressive movements sometimes motionless. 



Biological Characters not determined. 



FIG. 245. FIG. 246. 



FIG. 245. Spirillum volutans. X 600. (Cohn.) 

 FIG. 246. Spirillum sanguineum. X 600. (Cohn.) 



416. SPIRILLUM SANGUINEUM. 



Synonym. Ophidomonas sanguinea. 



Found in brackish water containing putrefying marine algae. 



Morphology. Rigid spiral filaments with round ends, 3 n or more thick, 

 and having two to two and one-half spiral turns, each 9 to 12 /* long ; the 

 protoplasm, contains numerous refractive red granules. 



FIG. 247. Fio. 848. 



FIG. 247. Spirillum serpens. X 650. (Flugge.) 

 FIG. 248. Spirillum tenue. X 650. (Flugge.) 

 FIG. 249. Spirillum uudula. X 650. (Flugge.) 



FIG. 849. 



417. SPIRILLUM SERPENS (Muller). 



Synonym. Vibrio serpens. 



Found in stagnant water, vegetable infusions, etc. 



Morphology. Rigid filaments having two or three wave-like undulations, 

 from 11 to 28 n long and 0.8 to 1.1 u thick; sometimes united in chains. 

 Actively motile and often associated in closely crowded swarms. 



Biological Characters not determined. 



