48 
THE STORY OF THE OAK TREE 
can boast chlorophyll as part of its armor to fight its 
way through life. 
But the man with the microscope can dip from sea 
water tiny one-celled creatures which he cannot call 
either plants or animals, because they are as much one as 
the other. To the animal kingdom and the plant king¬ 
dom belong wee free-swimming creatures, mere pieces 
of protoplasm without a cell-wall, from which whole 
families of creatures can be traced in both directions— 
into the animal kingdom and into the plant kingdom. 
At the outset, then, our 
friend the oak tree is 
the same as any simple, 
less bulky plant—the same 
as a violet, for instance. 
Each commences life as 
a tiny, naked protoplast 
(this means a piece of 
protoplasm) cuddled away 
inside the parent flower. 
When the time is ripe, 
the oak tree cell puts on 
its protective skin, the 
cell-wall. Very soon the cell divides, and the single cell 
gives rise to a chain of cells and this in turn to a cell- 
Dry Empty Wood Cells, 
Without Nuclei 
The pith of our oak tree is made up 
of just such cells as these. You can 
see why the first man with the micro¬ 
scope called them “cells;” they are 
fitted together just like the cells of 
a honeycomb. 
