CHAPTER XXX 



GERMINATION OF SEEDS 



From our study of flowers we know that fertilization 

 results in a seed. We are now ready to find out what a 

 seed is, and what it does. 



In preparation for this lesson soak a number of large 

 beans in water overnight. Keep a few of the dry beans 

 for comparison. Remove the covering from a soaked 

 bean. What is inside? These two thickened bodies 

 are called seed leaves. The short rodlike sprout is 

 called the hypocotyl. What do you find at the inner 

 end of the hypocotyl? This little bunch of leaves is 

 the plumule. These three things, the seed leaves, 

 the hypocotyl, and the plumule comprise the little plant- 

 let in the seed. If we wish to be exact we shall call 

 it the embryo. Another name for the seed leaves is 

 cotyledon. A plant whose embryo has two cotyledons 

 is called a dicot. How does the soaked seed differ 

 from the dry one? Can you find the place where the 

 water entered? 



What does each part of the embryo produce? To 

 answer this, plant some of the beans in moist sand or soil. 

 These may be planted several weeks before time for the 

 lesson. Do the seed leaves come up above the ground? 

 What becomes of them ? Why do they slowly shrivel up ? 

 The food stored in them is being used up in feeding the 



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