CHAPTER IX 



The Root 



The stem is the part of the plant that grows 

 upwards and needs air and light ; the root 

 grows downwards and requires the earth and 

 darkness. The extremities of its numerous 

 subdivisions are in a constant state of 

 growth, always young and soft, and there- 

 fore, well adapted for absorbing like a sponge 

 the liquids with which the ground is saturated. 

 It is to record this power of absorption that 

 the extremities of the roots, which are con- 

 stantly renewed, are called spongioles. The 

 spongioles come at the end of the rootlets 

 or final subdivisions of the root. 



There are two principal types of the various 

 forms of the root. Sometimes it consists 

 of a single growth or tap, which produces 

 branches as it penetrates deeper into the 

 ground. This is called a tap root. Some- 

 times it is a bunch or sheaf of simple or 

 branched members, which all beginning at 



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