12 ROOT. 



Hence the preservation of the spongioles in 

 an uninjured state is essential to the removal of 

 a plant from one place to another, and care 

 should be taken to preserve even the smallest 

 fibres of the roots uninjured. 



A Spongiole consists of very young vascular 

 tissue, surrounded by very young cellular sub- 

 stance. 



It is therefore one of the most delicate parts 

 of plants, and the most easily injured. 



Hence whatever is known to produce any 

 injurious action upon leaves or stems, such as 

 certain gases and mineral or vegetable poisons, 

 will produce a much more fatal effect upon the 

 spongioles. 



These spongioles have no powder of selecting 

 their food, but will absorb whatever the earth 

 or air may contain, which is sufficiently fluid 

 to pass through the sides of their tissue. 



So that if the spongioles are developed in a 

 soil which is of an unsuitable nature, as they 

 will still continue to absorb, they cannot fail to 

 introduce matter which will prove either in- 

 jurious or fatal to life, according to its intensity. 



This may often explain why trees suddenly 

 become unhealthy, without any external appa- 

 rent cause. 



