268 SYLVAN WINTER. 



from the roots to supply all the requirements of 

 the plant. As it grows older, and gets larger, 

 the functions of the pith cease, and the activity 

 of the stream of nourishment which flows through 

 the sap-wood lessens the necessity for the existence 

 of the pith, which then sometimes almost disap- 

 pears, or, when it remains, dries up and ceases to 

 take any part in the life of the plant. It may, 

 indeed, be assumed that the real ofl&ce of pith is 

 to nourish the leaves, flowers, and fruit of plants, 

 because pith is always present in an active form 

 in all branches or twigs that bear leaves, flowers, 

 or fruit. As soon as these, by growth and 

 development, have become so large and woody 

 as to cease to bear leaves or flowers, and only 

 give rise to other branches, thereupon their pith 

 commences to dry and lose its utility. In Winter, 

 therefore, there are two forms of pith that are 

 interesting — the big central column, which, if it 

 has not disappeared, has lost its vitality ; and the 

 new columns in branch and shoot and spray, not 

 active, but dormant, and waiting the awakening 

 force of spring to force it into active life. 



