REPRODUCTION OF BACTERIA 



47 



by loss of the power of locomotion in motile forms, the formation 

 of small, highly refractile granules within the cell. These 

 granules assume the appearance of globules and coalesce either 

 in the middle, at the end, or very near the end of the cell. The 

 coalesced globule thus formed increases in size and becomes 

 spherical or spheroidal in shape (Fig. 32). The spore never 

 becomes as long as the bacterial 

 cell, but frequently becomes 

 many times broader, thus distend- 

 ing the cell wall. The spore does 

 not always distend the rod. 

 When the spore is greater in FIG. 32. Spore formation. After 

 diameter than the mother cell and 



is in the center of the rod, a spindle-shaped appearance may 

 be produced (B. butyricus). If it is at the end of the cell, the 

 common drumstick form is produced (B. tetani). Occasion- 

 ally, when the spore is located a slight distance from the 

 end of the cell, the appearance of the cell is that of a wedge. 



This last-men- 

 tioned formation 

 is not character- 

 istic for any one 

 species but re- 

 sults rather as a 

 / "sport" (Fig. 33). 



FIG. 33. Spore formation showing various positions of 



spores. Original. j s f u lly formed, 



