38 
THE STEM. 
creeping root (see Fig. 16). A tuber is by modern botanists 
considered as a thickened stem produced by the approximation 
of the nodes, and the swelling of the internodes, as in the 
potato. The ordinary herbaceous stems of the potato, wlien 
cut into slips and planted, sometimes form branches from its 
base, which assume the form of tubers. A GOQ''m is a solid, un- 
derground stem which does not spread by sending out shoots, 
but remains of a rounded form, and is covered with thin scales 
on the outside. It is distinguished from a root by sending ofi 
annually buds, or thickened branches, either from the apex or 
side. These buds feed on the original corm, and destroy it. 
The runner is a slender, prostrate stem sent off from the base 
of the parent stem, capable of forming a new plant, as the 
runners of the strawberry. A sucker is an erect branch from 
the subterranean part of the stem, VN^hich first produces leaves, 
and afterward roots, as the rose. A stolon is a branch from 
the low^er part of a stem, which falls to the ground and takes 
root. An offset is a short prostrate branch terminated by a tuft 
of leaves and capable of taking root, as the house-leek. 
44. A remarkable phenomenon is described by travelers, as exhibited by the 
atems of the Banyan-tree of India {Ficus Indicus) ; these stems throw out fibers^ 
which descend and take root in the earth. In process of time they become large 
trees ; and thus 
from one primitive 
root is formed a 
little forest. This 
tree is called by 
various names; as 
the Indian-God- 
tree, the arched- 
Fig-tree, &c. The 
Hindoos plant it 
near their temples, 
and in many cases, 
the tree itself 
serves them for a 
temple. Milton 
speaks of this tree, as the one from -which Adam and Eve obtained leaves to form 
themselves garments ; he says it was not the fig-tree renowned for fruit, but 
Such as at this clay to Indians known 
In Malabar or Decan, spreads her arms. 
Branching so broad and long, that in the ground 
The bended twigs take root, and daughters grow 
About the mother tree, a pillar'd shade 
High overarched, and echoing walks between." 
Thi^ wonderful tree (Fig. 31) is said to oe capable of giving shelter to severai 
thousajid persons. 
45. All varieties of stems belong to two classes : 1st, such as 
grow externally^ having their wood arranged in concentric 
layers, the oldest being in the center of the trunk, and the 
newest forming the outer layer ; as may be seen in the oak, 
44. Banyan-tree. — 45. Dicotyledonous stems. 
