The Stem 111

contains sugar, which is chiefly for distribution of the
seed, but may form humus.
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QUESTIONS ON CHAPTER IV.

1. Compare roots and stems with regard to structure,
function, tropisms.
2. Give examples of herbs, shrubs, and trees. What points
of likeness and difference do you note?
3. How would you distinguish the poplar, oak, willow, ash
and elm in winter time?
3. Describe the means by which plants climb. What is the
advantage of the climbing habit?
4. Define tuber, bulb, corm, rhizome, stolon, sucker, runner,
off-set. What is the advantage of the rhizome habit?
5. Describe the structure of an onion bulb and of a potato
tuber.
6. Describe the stools of the dahlia and canna.
7. Compare one0year old, three-year-old, and ten-year-old
stems of any available tree.
8. What are the advantages and disadvantages of prostrate
stems? Decribe any prostrate stems you know.
9. Draw sections of one-year old monocotylous and dicotyl-
ous stems. Compare the arrangement of the tissues.
10. What advantage have hollow over solid stems?
11. Describe the structure of an ordinary bud.
12. Compare spring and autumn wood.
13. In what plants are the stems eaten, and in what others do
the stems yield useful substances?
14. Give a tabular classificiation of stems.
15. Distinguish epiphytes and parasites. What are the com-
monest epiphytes and parasites in New Zealand?
16. What are the fundtions of bast, wood, cortex, and
epidermis?
17. How would you distinguish the following trees in winter;
- ash, pinus insignis, plum, apple, pear, peach?
18. Name three native tress with which you are familiar
Describe their habit, branching, buds, and bark.
19. What is a growing point? Compare the growing points of
roots and stems.