236 
THE PLANT WORLD. 
C. The bud. 
1. Structure (protective coverings). 
2. Arrangement on stem (flower, leaf). 
3. Function. 
4. Propagation by (shield and T budding). 
5. Disbudding to increase size of flowers. 
D. The flower. 
1. Structure. 
2. Function. 
3. Cross-fertilization and hybridizing. 
4. Selection for seed purposes. 
5. Changing color and shape by selection. 
6. The increase of size, number and quality in cultiva¬ 
tion. 
Section III. Descending portion of plant. 
A. The root. 
1. Function (absorption of nutriment to anchor plant). 
2. Structure. 
3. Region of growth (root-cap). 
4. Absorptive region (root-hairs). 
5. Conductive portion. 
6. Relation of root to oxygen. 
7. Absorption of liquids (osmosis). 
8. Passage of liquids; root pressure. 
9. Use for propagation (cuttings, grafting). 
10. Care of roots in culture. 
B. Soils. 
a. Mechanically considered. 
1. Early formation; cooling, decomposition, gla¬ 
ciers, organic matter, life, disintegration of 
rock.* 
2. Structure (analysis). 
3. Use of soils. 
(a) Reservoir for storing water. 
( b ) Laboratory in which changes are taking 
place. 
4. As water retaining medium. 
