250 NATURE STUDY AND AGRICULTURE 



growing plant. What does the hypocotyl make? The 

 pupil will be interested to see that the lower part of it 

 makes root, while the upper part makes stem. What has 

 the plumule become? Plant some pea seeds. Do the 

 seed leaves come above the ground ? 



Soak some corn seeds at least twenty-four hours. 

 Compare the dry seed with the soaked one. What part 

 of the seed' has been changed? This shows where the 

 germ or embryo is located. Remove the covering from the 

 soaked grain. You can now see the germ, which is dirty 

 white in color. With a knife dig this out of the grain. 

 You will find that instead of two seed leaves or cotyledons 

 this has but one. Plants whose seeds have but one cotyle- 

 don are called monocots. 



Cut the embryo open to find the rodlike hypocotyl and 

 plumule. Which end is plumule? Which hypocotyl? 

 To determine this, place a few soaked grains on some moist 

 blotting paper or sand on a plate. Turn another plate 

 over this. Keep moist. In a week the seeds will be 

 ready to answer the question. 



Is there much of the grain of corn left after the embryo 

 is removed? This is called the endosperm. What is it 

 for? Leave this as a problem to be solved later if 

 there is any doubt in the minds of the pupils. 



What conditions are necessary for the germination of 

 seeds? For the following experiments beans, peas, or 

 corn are good. Soak five seeds, place them on moist 

 blotting paper in a cup, and set in a warm place. Treat 

 five other seeds in exactly the same way, but place the cup 

 in a very cool place. If some one has a refrigerator, have 

 it placed in this. Be sure to keep both moist but not wet. 



