CHAPTER: Vi 
STRUCTURE OF THE STEM 
STEM OF MONOCOTYLEDONOUS PLANTS 
96. Gross Structure. — Refer back to the sketches of the corn- 
seedling, to recall something of the early history of the corn-stem. 
Study the external appearance of a piece of corn-stem or bamboo 
two feet or more in length. Note the character of the outer surface. 
Sketch the whole piece and label the enlarged nodes and the nearly 
cylindrical internodes. Cut across a corn-stem and examine the cut sur- 
face with the magnifying glass. 
Make some sections as thin as 
they can be cut and examine 
with the magnifying glass 
(holding them up to the light) 
or with a dissecting microscope. 
Note the firm rind, composed 
of the epidermis and underlying 
tissue, the large mass of pith 
composing the main bulk of the 
stem, and the many little harder 
and more opaque spots, which 
are the cut-off ends of the 
woody threads known as /ibro- 
vascular bundles (Fig. 52). 
Split a portion of the stem 
lengthwise into thin translucent 
slices and notice whether the 
Fig. 52. — Diagrammatic Cross-Section 
of Stem of Indian Corn. 
cv, fibro-vascular bundles ; gc, pithy material 
between bundles. 
bundles seem to run straight up and down its length; sketch the 
entire section x 2. Every fibro-vascular bundle of the stem passes out- 
ward through some node in order to connect with some fibro-vascular 
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