204 BOTANY: PRINCIPLES AND PROBLEMS 



552. What advantages and what disadvantages are there in insect- 

 poUination ? 



553. The corollas of most flowers are some other color than green. 

 Explain. 



554. Why are low-growing plants almost always pollinated by 

 insects? 



555. Alpine flowers are usually brilliant in color or otherwise conspicu- 

 ous. Explain. 



556. Night-blooming flowers are usually white. Explain. 



557. Low-growing and inconspicuous flowers are often very fragrant. 

 Explain. 



558. In many plants, the flowers are arranged in clusters. Of what 

 advantage is this to the plant? 



559. In most flower clusters, the flowers open a few at a time rather 

 than all at once. Explain. 



560. Are solitary flowers usually larger or smaller than those which 

 occur in clusters? Explain. 



561. Do you think that bees are attracted to flowers by the same 

 odors which are attractive to human beings? Do you think that the 

 same holds true for flies? Explain. 



562. Most flowers do not exceed a decimeter in diameter and the great 

 majority are very much smaller. Can you explain whj^ flowers are 

 commonly not larger than this? 



563. Many flowers are so constructed as to admit be'^'' readily but to 

 exclude ants. What does the plant gain by this? 



564. It is a general rule that plants rich in nectar tend to have hairy 

 stems and flower stalks. Explain. 



565. In many plants, the removal of the stamens as soon as the bud 

 opens often causes the flower to remain in bloom longer than it would if 

 the stamens were left attached. Explain. 



566. What means of dispersal have plants aside from the dispersal of 

 their seeds? Give examples. 



567. Other things being equal, which type of plant will become dis- 

 persed more rapidly, a tree or an herb? Explain. 



568. What advantage is it to a berry-bearing plant to have its fruits 

 brightly colored? 



