THE SKKD 27 



till it strikes a soft spot, when it begins at once to bore its 

 way into the ground. The common peanut is another exam- 

 ple. The blossoms are borne under the leaves, near the base 

 of the stem, and as soon as the seeds begin to form, the 

 flower stalks lengthen several inches, carrying the young pods 

 down to the ground, where they bore into the soil and ripen 

 their seeds. 



Practical Questions 



1. Name the ten most troublesome weeds of your neighborhood. 



2. What natural means of dispersal have they ? 



3. Which of them owe their propagation to man ? 



4. Are there any tumbleweeds in your neighborhood ? 



5. Would you expect to find such weeds in a hilly or a well-wooded 

 region? (19, 23; Exp. 17.) 



6. What situations are best fitted for their propagation? (19, 23; 

 Exp. 17.) 



7. Make a list of all the fruits and seeds you can think of that are 

 adapted to dispersal by wind ; by water ; by animals. 



8. By what means of dissemination, or protection, or both, is each of 

 the following distinguished : the squash; apple; fig; pecan; poppy; 

 bean ; beggar-tick ; linden ; grape ; rice ; pepper ; olive ; cranberry ; 

 jimsonweed; thistle; corn; wheat; oats? 



9. What is the agent of dispersion, or what the danger to be provided 

 against, in each case ? 



10. Could our cultivated fruits and grains survive in their present state 

 without the agency of man ? (22.) 



11. Name all the plants you can think of that bear winged seeds and 

 fruits ; are they, as a general thing, tall trees and shrubs, or low herbs ? 



12. Name all you can think of that bear adhesive seeds and fruits ; are 

 they tall trees or low herbs ? 



13. Give a reason for the difference. (Exps. 17, 20.) 



14. Why is the dandelion one of the most widely distributed weeds in 

 the world? (19; Exp. 17.) 



15. Is the wool that covers cotton seed for dispersal or protection ? 



16. What advantage to the Indian shot (canna) is the excessive hardness 

 of its seeds? (21.) 



17. What is the use to the species, of the bitter taste of lemon and 

 orange seed? (21.) 



18. Why are the seeds of dates and persimmons and haws so hard? 

 (21.) 



