72 THE GERM THEORY OF DISEASE. 



SPORES HABITS. 



It seems well demonstrated that a number of the lower 

 forms of life, bacteria, mycoderma, saccharomyces, etc., form 

 their spores under conditions other than those best suited to 

 the active growth of the plant. From a close scrutiny of the 

 manner and time of spore formation of these life forms, it 

 seems that they are formed only under conditions which 

 slowly destroy the activity of the plant. The yeast plant 

 forms spores only after fermentation has ceased and its multi- 

 plication by budding hindered. It has been asserted that the 

 bacillus anthracis will form spores in the cultivation flasks 

 only when the temperature has been allowed to fall below 

 that of the blood, and, therefore, cannot form them until 

 eliminated from the animal in which they grow, or after the 

 death of the animal. 



A considerable number of organisms, whose natural habitat 

 seems to be fruits, such as grapes, cherries, etc., form spores 

 only when drying occurs ; that is, the plant lives on the fruit, 

 multiplying by budding or by fission ; but when the fruit 

 gives out and drying up begins, the formation of spores begins 

 also. This seems to be the controlling factor in spore forma- 

 tion in a large number of the bacterial forms. And the 

 philosophy of this act, when we consider it, is rather beau- 

 tiful, and would seem to be a special fitness of function to 

 needs. Rapid multiplication by the simple plan occurs in the 

 presence of suitable conditions for activity. When these con- 

 ditions begin to fail comes the organization of the spores 

 destined to preserve vitality under conditions unfit for active 

 growth. 



The facts now at our disposal will not warrant the conclu- 

 sion that this is a law of spore formation for all these organ- 

 isms. Indeed, we have facts which directly controvert this 

 proposition. 



