70 THE PLANT: A GENERAL EXTERNAL VIEW 



know by their flowers. 3. Define petal, corolla, sepal, calyx, stamen, 

 anther, pollen, pistil, ovary, stigma, style. 4. Do all flowers have 

 the same function ? If so, what is it ? 5, Do you know any kind of 

 plant which produces more than one kind of flower ? If so, describe 

 it. 6. Have you ever noticed flowers on trees ? If so, describe some 

 kind you have noticed. 7. Does corn have flowers? Wheat? Grass? 

 8. Why do insects visit flowers ? 9. Are the visits of insects to flowers 

 of any advantage to the plants ? 10. Are the bright colors of flowers 

 of use to the plant ? Is trie fragrance of the flowers of use to the plant ? 



11. Do the commonest plants have bright and fragrant flowers? 



12. At what season are wild flowers most abundant? 13. Are wild 

 flowers in the fall found most abundantly in the places in which they 

 are found most abundantly in the spring, or in different places ? 



Section 20. 1. What is the botanical definition of the word fruit ? 

 2. Is it of advantage to a plant to produce a fruit which is eaten by 

 animals? 3. Write a list of edible fruits produced in temperate 

 regions. 4. Write a list of edible fruits produced in the tropics. 



5. What is meant by dissemination ? Of what advantage is it to a 

 plant ? 6. Give examples of fruits which are scattered before they 

 open and set free the seeds. 7. Give examples of fruits which open 

 before the seeds are scattered. 8. What are the first wild fruits 

 which you have noticed in spring ? 9. What plants have you noticed 

 whose fruit hangs on through the winter ? 10. Describe various ways 

 in which animals aid in scattering fruits. 



Section 21. 1. What is the chief function of seeds ? 2. What are 

 the three principal parts of a seed ? 3. Define cotyledons and endo- 

 sperm. 4. What plants have you noticed which produce seeds in 

 great numbers ? 5. Do you think' it better for a plant to produce a 

 smaller number of large seeds or a larger number of small seeds ? 



6. When we speak of the "most successful" plants we mean those 

 plants which, without the aid of man, are the most common. That 

 is, it is by abundance that we judge a plant's "success" in a general 

 way. Do the most successful plants that you have noticed produce 

 great numbers of small seeds or small numbers of comparatively 

 large seeds ? What other properties besides size have you noticed 

 to be characteristic of the seeds of the most successful plants? 



7. Make a list of seeds which are used by man for food and for other 

 purposes. 8. What conditions are necessary to cause a seed to sprout ? 



