DUCKWEED 



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Duckweeds increase in number by new leaves that grow 

 from the edges of the old ones. Do you find any of the small 

 new leaves on the plants that you observed ? 



Duckweed and a Snail 



Leaf Shapes of Water Plants. — Besides duckweed, what other 

 plants have you seen growing with their leaves afloat on the 

 top of the water ? What is the shape of the leaves of pond 

 lilies ? What is the shape of most floating leaves ? 



Do you find any plants having some of their leaves floating 

 on the water, and other leaves growing under water ? How 

 do these two sets of leaves differ in shape ? 



How stiff is the stem of a pond lily ? Why does a pond 

 lily not need a stiff stem ? What is the stiffness of the stems 

 of most plants that float on the water or grow beneath it ? In 

 what way might stiff stems be bad for the plants ? How stiff 



