62 THREE KINGDOMS. 



exterminate. Try to find out their original home 

 by reference to books. 



XVII. Make a list of the flowering times of our com- 

 monest plants. Repeat this next year and note 

 whether the dates are the same ; if not, why ? 



XVIII. Note the ways in which plants protect them- 

 selves against cold, rain, insects, or other ene- 

 mies ; study thorns, prickles, hairs, wax, bad 

 odors, etc. 



XIX. Relations of plants to each other; helpful, harmful. 



XX. Relations of animals to -plants; helpful in distrib- 

 uting seeds or carrying pollen ; harmful in de- 

 stroying leaves, buds, fruits, roots, etc. 



XXI. Relation of wind and water to plants ; carrying 

 pollen, seed, roots, etc. Wind bringing rain, rain 

 dissolving food in ground, etc. 



XXII. Climbing plants j make list of those found ; study 

 their ways and means and habitats ; note how the 

 same end may be attained in very different man- 

 ners ; observe how trees and other objects on 

 which they grow are affected. 



XXIII. Study those plants that bloom before their 

 leaves appear; those whose flowers and leaves 

 appear together; try to understand the advan- 

 tages of such habits. 



XXIV. See why insects visit flowers, how they are 

 attracted, of what use they are to the plant, and 

 what various mutual adaptations have taken place. 

 Note whether insects visit only certain flowers, or 

 any indiscriminately ; find out whether they can 

 distinguish colors or the fragrance of blossoms. 

 Note how cross- fertilization is also carried on in 

 other ways, by wind, birds, etc. 



XXV. Study the phyllotaxy, not alone of trees, but 

 also of shrubs and herbs, as well as flower-clusters 

 and fruits. Those who take pleasure in mathe- 



