FAMILY VII. SPIRILLACEAE 



261 



When the gelatinous mass disintegrates, 

 swarm cells are formed which are pre- 

 sumably polar flagellate. The individual 

 cells are granular and stain rather poorly. 

 During reproduction, the filaments be- 

 come somewhat elongated and expand the 

 gelatinous mass to an ellipsoidal shape. As 

 the gelatinous sphere undergoes transverse 

 fission, there is a concomitant division of the 

 filament, the daughter cells finally separat- 

 ing from each other. Lankester (Quart. 

 Jour. Micros. Sci., 13, (N.S.), 1873, 408) 

 erroneously believed this gelatinous form 



to be a stage in the life cycle of a Spii-ilhim, 

 probably Spirillum undula Ehrenberg. 



These organisms have not been cultivated 

 on artificial media. 



Source : Found in the surface scum of sul- 

 fur-water in a jar with decomposing algae, 

 especially Spirogyra sp. (Cohn, op. cit., 

 1875, 183). Also found by Migula {op. cit., 

 1900, 960) in peat bogs between Weingarten 

 and Karlsruhe. Hansgirg (Osterr. Vot. 

 Ztschr., 38, 1888, 265) frequently found this 

 organism among his algal cultures in Bo- 

 hemia. 



Habitat: Fresh-water ponds. 



