CHAPTER VI 



FURTHER CHARACTERS OF THE BACILLUS 



One of the important points in the life-history of a 

 bacterium in general, and of pathogenic microbes in 

 particular, is the question of spore formation. A 

 bacterium that is possessed of the power of forming 

 permanent, seeds or spores possesses at the same time 

 the power of preserving vitality and of insuring new 

 generations to a far greater extent than one that is 

 not possessed of this power, because spores are, as a 

 rule, capable of retaining their vitality and the power 

 of germinating under conditions and circumstances 

 such as easily affect the vitality of non-spore-bear- 

 ing forms, e.g. heat, cold, drying, absence of suf- 

 ficient nutriment, chemically obnoxious substances. 

 While it is well known that continued cold, even 

 if above freezing-point, or heat far below the point 

 of boiling water (even 55° C), acting for many hours, 

 or deficiency of nutriment, drying, acids and alka- 

 lies, affect considerably the vitality of non-spore- 

 bearing forms — many in fact perishing under those 



