HOW PLANTS FEED 25 
immediately below it—whether the leaf-scar is visible or 
not. 
Norr.—The suggestions contained in this chapter will furnish 
material for work in Standard III. and higher classes. The 
subject of leaf-arrangement is one involving a considerable amount 
of difficulty for children and should be confined to the investigation 
of very simple cases. The earlier lessons should aim at leading 
pupils to see that leaves and branches are arranged on plants in 
conformity with fixed plans, and that the methods of arrangement 
can be discovered by investigation. The more difficult cases — if 
dealt with at all—should be deferred until pupils have reached 
Standard V. and Standard VI. 
The importance of leaf-arrangement will afford a good oppor- 
tunity of helping pupils to realise how effectively Nature works to. 
secure the objects she has in view. 
VII.—HOW PLANTS FEED. 
Plants obtain food from the ground through their roots, 
and from the air through their leaves. The food, which 
must be in a dissolved state, enters the root through the 
fibres and root-hairs and gradually passing up the stem 
finds its way to the leaves; here the water is evaporated 
from the surface of the leaves, and the mineral and other 
matter carried by the water is left behind. From the air 
the plant obtains a supply of carbon-dioxide, which enters 
the small openings or pores on the leaves, and which in the 
presence of sunlight is decomposed into carbon and oxygen 
—the oxygen being sent out into the air and the carbon 
being retained—the air, in fact, is the sole source from 
which plants draw their supplies of carbon. The food 
which has been brought up from the root and the carbon 
derived from the air are next manufactured by the leaves 
into the substances required by the plant—one of these 
being starch. These substances then pass back from the 
