320 



GENERAL SCIENCE 



produced by nature to furnish food for the new plants 

 or to protect the seeds from climatic conditions until 

 a favorable time for growth shall arrive. 



Dispersal of Seeds. A little observa- 

 tion will disclose to any one a number 

 of ways in which seeds are dispersed. 

 Hold a maple seed high in the air and 

 notice whether it falls directly to the 

 ground or not. What is the value of 

 wings on maple seeds? Some seeds like 

 the dandelion and thistle are provided 

 with little parachutes (pappus) which 

 FIG. 277. stamens enable the wind to carry them for long 



and Pistil. distances (Figure 280). 

 Some plants, such as tumbleweeds, break from the 

 main stem and are then blown along the 

 ground, scattering seeds as they go. 



Squirrels, birds, and other animals are active 

 agents in the dispersal of seeds. 



Germination of Seeds. - - The stages passed 

 through by a young plant from the time it 

 begins to sprout until it becomes an inde- 

 pendent plant are called germination. 



The process of germination may be studied 

 by planting some seeds of various kinds. 

 Plant some beans, squash seeds, corn, and 

 wheat in warm, moist soil or sawdust and ob- FIG. 278. A 

 serve them from day to day. Some of each simpleF 

 kind of seeds should be left untouched until the plant 

 appears above the surface of the soil. Do they all come 

 out of the soil in the same way? (Figure 281.) 



As the embryo plant in the seed begins to grow, it again 

 bursts open the seed leaves. These seed leaves contain 



