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SECOND BOOK. 
2. Outside and around the germ (as in corn, cocoa-nut, and coffee). 
In the former case the young plant forms the entire kernel of the seed; in the 
latter it forms only a small portion of it. 
Conditions- — In order to germinate, a seed must have — 
1. Moisture ; which causes the seed to swell and to burst its skin. 
2. Warmth ; some seeds require much greater warmth than others 
3. Air; from which the seed obtains oxygen gas. 
HOW A PLANT FEEDS (pp. 68-74). 
Plant-food is derived from — 
1. The Air ; through the leaves and green stems. 
2. Water ; through the leaves, stems, and roots. 
3. The Soil ; through the roots. 
From the atmosphere and water plants can obtain oxygen, hydrogen, 
carbon, and some nitrogen. The rest of the nitrogen required, and all the 
mineral substances, are taken from the soil. 
Water consists of oxygen and hydrogen. 
The air consists mainly of oxygen and nitrogen. In it are small quantities of — 
1. Carbonic-acid gas, containing oxygen and carbon ; and 
2. Ammonia and nitric acid, containing nitrogen and hydrogen. 
The Roots- — Numbers of the cells of the root -fibres lengthen out 
like hairs. These root-hairs absorb water and dissolved plant-food. 
The Leaves: 
1. They feed on the carbonic acid, nitric acid, and ammonia of the air. 
2. They keep the carbon of the carbonic acid, and give out the oxygen 
(assimilation). 
3. They breathe ( respiration ); that is, they take in oxygen and give 
out carbonic acid, though the latter is much less in quantity than the 
oxygen given out in sunlight. 
4. They give off water (transpiration). 
HOW PLANTS ARE REARED (pp. 74-79). 
Plants may be reared by various means, viz. — 
1. By Seeds. We should select the finest seeds from the best plants. 
2. By Bulbs ; e.g . onions. 
3. By Tubers; e.g. yams. 
4. By Runners ; having a bud at the end of a slender stem. 
5. By Suckers ; or shoots from underground stems, as in bananas 
6. By Buds ; as in the root-stock of ginger. 
