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FLOWER-LAND, 



growing state the cell contains a soft substance, alive ; 

 that is. with power of growth, which is called 

 "protoplasm" * In these plants which you are learn- 

 ing about, it has a special part called a nucleus ; its 

 skin or covering is the cell wall, and the watery fluid 

 which is found in cells is called the cell sap, about 

 which I will tell you a little more in due course. 



Now, how do cells increase in number ? When 

 you learn about the flowerless plants, you will find 

 that sometimes old cells become young again, or two 



Fig. 143. Various kinds of cellular tissue 

 (parenchyma}. 



or more join together to form a new cell : but now 

 remember that cells increase in number by division. 

 You will learn in due course about the different ways 



* From the Greek "protos," first, and "plasma," anything moulded 

 or modelled. 



