26 THE GROWTH AND PARTS OF. PDANTS 
developed. What are the advantages to the plant of 
the distribution of the roots which you observe ? 
Growth of the stem. 
4 as 
» In a similar way the re- 
fr} Pay P= 
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gion over which growth 
extends in the stem may 
be shown. As soon as 
the seedlings come above 
the ground, or as soon 
as a new portion of the 
shoot begins to elongate 
above the leaves, mark 
off the stem with cross 
lines. The lines on the 
et oe ay ee 
farther apart than those 
on the root. They may be put as indicated in Fig. 90. 
A rule may be used to locate the marks on the stem, 
and then, after several days, if the rule is placed by 
the side of the stem, the amount of growth will be 
determined. 

