PALMS BUILD CHIMNEYS 
come up through it, and the tree will grow only at the 
top. 
The palm, in growing this way, is unique among trees. 
It borrowed the idea, it would seem, from members of 
the grass family. The grasses are inside growers. The 
stalk of the tall bamboo, which is a grass, never increases 
its diameter. The members of the lily family also are 
inside growers. They add to their tops but not to the 
outside of their stalks. The yucca is a giant lily that 
comes near being a tree. It grows only at the top. 
The grasses, the lilies, and the palms, therefore, seem 
to be more nearly related to one another than they are to 
such other plants as hickory trees and rose bushes. All 
have sheath leaves that are attached to their trunks. A 
stalk of corn, which is a coarse grass, has leaves that are 
attached to it in a sheath, much as those of the palm are 
attached to its trunk. Even the leaves of the grasses, 
lilies, and palms are similar in a general way. They are 
blade-like. These inside growers are evidently kinsfolk. 
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