THE LIVING STRUCTURES 



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precisely in the same manner that the cells run and take 

 care of the individual they inhabit, be it animal or plant. 

 Think of that invisible crab ! How are the cells able to 

 build themselves into a structure so as to be transparent? 

 Those are secrets for us to solve. 



FIG. 23. A submarine made by the cell. 



I must not forget the African fish that constructs a 

 moisture proof house in the mud where it sleeps for six 

 months, during the dry season, living on its own fat 

 gathered during its activity. It is described as follows : 

 "A remarkable fish known as protopterus annectens is 

 found throughout the whole of tropical Africa, but is 

 most common near the West coast, where it sometimes 

 attains a length of six feet. During the dry season, when 

 many of the ponds dry up, the fish descends some dis- 

 tance into the mud and forms a rounded hollow for a 



