134 SYMBIONTICISM AND THE ORIGIN OF SPECIES 



that gave rise to the protozoa and algae, originate as the 

 result of environmental influences, or are they the result 

 of some other factor. We have maintained, and the 

 evidence submitted by many observers supports the con- 

 tention, that bacteria are changed or modified by environ- 

 mental influences. To what limits these modifications 

 may proceed is not known. Most bacteria, perhaps, con- 

 tain chromatin diffused in the bacterial body. Some of 

 the higher bacteria appear to possess a more or less distinct 

 nucleus. It is not known whether or not these are true 

 nuclei. The evidence appears to favor their true nuclear 

 character. Other bacteria contain granular masses within 

 the bacterial body that have the staining properties of 

 chromatin. The variations of chromatin material in the 

 bacteria, from a more primitive diffused state to that in 

 which it appears as a true nucleus, seems to indicate a 

 gradual developmental process. It might appear that 

 in such simple forms nothing but environmental influences 

 could have brought about these variations. Such an hypo- 

 theses is further enhanced by the known fact that bacteria 

 are so sensitive to environmental influences. Neverthe- 

 less, we venture to advance a different hypothesis of the 

 nature of the mechanism whereby the one-celled plants 

 and animals may have been derived from the bacteria. 



It is not only conceivable that prototaxis was in opera- 

 tion in these early stages of evolution, but that this factor 

 must have originated when Ufe itself began. It is then 

 logical and reasonable to assume that bacteria of different 

 strains responded to positive prototaxis by fusing into a 

 single mass or entity. In such a "fusion bacterium," at 

 least two chromosome- and cytoplasm-complexes united 

 to form an organism of an order higher than that of either 

 component. It is also conceivable that further prototactic 

 fusions took place between the more complex bacteria and 

 the simpler ones. As the result of such fusion activities, 



