CHAPTER VII 
STRUCTURE OF THE STEM 
STEM OF MONOCOTYLEDONOUS PLANTS 
81. 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 inter- 
nodes. Cut across a corn-stem 
and examine the cut surface 
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 
Fic. 38. Diagrammatic Cross-Section 
of Stem of Indian Corn. 
ev, fibro-vascular bundles; gc, pithy 
material between bundles. 
the woody threads known as fibro-vascular bundles (Fig. 38, cv). 
Split a portion of the stem lengthwise into thin translucent slices 
and notice whether the bundles seem to run straight up and down 
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