40 PRACTICAL COURSE IN BOTANY 
abundant tillage? Why not on undrained or badly drained land? (Exps. 
26, 27.) 
7. Will seeds that have lost their vitality swell when soaked? (Exp. 16.) 
8. Are there any grounds for the statement that the seeds of plums 
boiled into jam have sometimes been known to germinate?! (33; Exp. 30.) 
9. Could such a thing happen in the case of apple or sunflower seed, 
and why or why not? (33.) 
10. Does it make any difference in the health and vigor of a plant 
whether it is grown from a large and well-developed seed or from a weak 
and puny one? (Exp. 33.) 
11. Would a farmer be wise who should market all his best grain and 
keep only the inferior for seed ? 
12. What would be the result of repeated plantings from the worst 
seed ? 
13. Of constantly replanting the best and most vigorous? 
14. Suppose seed would germinate without moisture; would this be 
an advantage, or a disadvantage to agriculturists ? 
15. Why is a cool, dry place best for keeping seeds? (Exps. 26, 29.) 
16. Why are the earliest tomatoes found in the market usually smaller 
than those offered later? (35.) 
17. Why is continued rain so :njurious to wheat, oats, and other grains 
before they are mature enough to be harvested? (35; Exp. 32.) 
18. Would the same effect be likely to occur in the case of very oily 
seeds, such as flax and castor beans? Why? (Suggestion: try the effect 
of putting water on a piece of oiled paper.) 
19. Explain why many seeds cannot germinate successfully without 
air. (30, 31; Exp. 25.) 
20. Mention some of the practical advantages that a farmer, a gardener, 
or a careful housewife might gain from experiments like those made in this 
section. 
21. Explain why seeds can endure so much greater extremes of tempera- 
ture than growing plants. (23, 33.) 
Il. DEVELOPMENT OF THE SEEDLING 
Materiau. — Seedlings of various kinds in different stages of growth. 
It is recommended that the same species be used that were studied in 
Section III, Chapter I, or such equivalents as may have been substituted 
for them. Enough should be provided to give each pupil three or four 
specimens in different stages of development. Seeds, even of the same kind, 
‘Vines, ‘‘ Lectures on the Physiology of Plants,” p. 282. See also Sachs, 
“Physiology of Plants.” 
