66 



Marine Microbiology 



Fig. 2. (2) Electron micrograph of Thiovulum, (3) Electron micrograph of 

 Thiovulum in the stage of constriction, (4) A veil of Thiovuhini cells 

 formed in a cell suspension in a cuvette. Photograph taken with reflected 

 light, (5) Micrograph of the edge of a mass of chemotactically aggregating 

 cells, (6) and (7) Micrographs of Thiovulum cells, containing various 



quantities of sulfur. 



