084 CONSTANCY AND MUTABILITY OF FUNGI. 



More than in any other scientific department is it 

 necessary to limit our judgment in the case of the lower 

 fungi to the particular species in question, and we are 

 just as little justified in declaring that a hereditary 

 attenuated condition of the hacteria is impossible, as 

 the result of theoretical considerations, as we would be 

 in deducing from a few instances in which such attenua- 

 tion has been proved that there is an extensive altera- 

 tion of virulence as the result of other influences, and 

 in the case of other species of bacteria, which have not 

 been tested, or that there is a similar variable condition 

 of all the other properties of the bacteria. 



