50 SOUTH AFRICAN BOTANY 
of one hundred feet. The cambium which appears be- 
tween the bundles is called INTERFASCICULAR CAMBIUM. 
28. The Stem of the Maize.—A section across the 
stem of the maize presents a very different appearance 
from that of the dicotyledonous stem described in the 
—_- : 
Fig. 33.—Transverse Section of Bundle from Stem of Mealie. 
p. Ground tissue. v. Phloem. g. Large pitted vessels of the xylem. 
s.. Spiral vessel, 17, Annular vessel. /, Air cavity (after Sachs), 
preceding paragraph. Instead of a central cylinder con- 
taining a ring of bundles we have a large number of 
bundles scattered irregularly about the whole section. 
The bundles themselves (fig. 33) also differ considerably 
from the open collateral bundles of the sunflower. They 
possess no cambium, but consist of xylem and phloem 
surrounded by sclerenchyma. Such bundles are called 
