134 VITALISM AND SCHOLASTICISM 



Yet is seems unlikely that the earliest plants 

 can have been chlorophyllaceous, since chloro- 

 phyll connotes a considerable advance in com- 

 plexity. In this connection it is interesting to 

 note that we have knowledge of bacteria which 

 can feed directly on inorganic substances such as 

 Nitroso- Nitrosomonas, a prototrophic bacterium which 

 nitrobacter as ^ s ^ orne * tells us, " for combustion . . . 

 takes in oxygen directly through the inter- 

 mediate action of iron, phosphorus or man- 

 ganese, each of the single cells being a 

 powerful little chemical laboratory which con- 

 tains oxidising catalysers, the activity of which 

 is accelerated by the presence of iron and 

 manganese. Still, in the primordial stage, 

 Nitrosomonas lives on ammonium sulphate, 

 taking its energy ( food) from the nitrogen of 

 ammonium and forming nitrates. Living sym- 

 biotically with it is Nitrobacter, which takes 

 its energy (food) from the nitrates formed by 

 Nitrosomonas, oxidising them into nitrites. 

 Thus, these two species illustrate in its simplest 

 form our law of the interaction of an organism 

 (Nitrobacter) with its life environment (Nitro- 

 somonas)." 



v It must be confessed that this very interest- 

 ing observation does not in any way help us 

 to find a materialistic explanation of life, nor 



* Op. cit.y p. 82. 



