THE STORY OF GERM LIFE. 



Fig. 17 shows a group of these Oscillariae, and 

 the similarity of this to some of the thread-like 



bacteria is de- 

 cided. The Os- 

 cillarice are, how- 

 ever, true plants, 

 and are of a 

 green colour. 

 Bacteria are 

 therefore to-day 

 looked upon as 

 a low type of 

 plant which has 

 no chlorophyll,* 

 but is related to 

 Oscillarice. The 

 absence of the 

 chlorophyll has 

 forced them to 

 adopt new rela- 

 tions to food, 

 and compels 



FIG. 17. Threads of Oscillaria, the nearest them to feed 

 allies of bacteria. 



upon complex 



foods instead of the simple ones, which form the 

 food of green plants. We may have no hesita- 

 tion, then, in calling them plants. It is interest- 

 ing to notice that with this idea their place in the 

 organic world is reduced to a small one systemat- 

 ically. They do not form a class by themselves, 

 but are simply a subclass, or even a family, and 

 a family closely related to several other common 

 plants. But the absence of chlorophyll and the 

 resulting peculiar life has brought about a curi- 



* Chlorophyll is the green colouring matter of plants. 



