PROBLEM 2. The Kinds of Plants of the Earth 93 



pieces of moist white blotting paper in bowls, expose some bread, apple, 

 lemon, cheese, and other kinds of food. Cover the bowls and keep them 

 at room temperature. Keep the blotting paper moist. After several days 

 begin to observe closely at short intervals. Describe what you see. Com- 

 pare with the results obtained by your classmates. Do certain kinds of 

 molds seem to grow best on certain foods.^ Where do the molds come 

 from .5 



4. If you crumble a small piece of yeast cake into water and mount a 

 tiny drop on a slide, you will be able to see the yeast cells under the 

 microscope. A magnification of about 400 times is necessary. 



5. How can you find out whether or not there are yeasts in the air? 

 Plan the experiment. Discuss your plan with your classmates and teacher 

 to make sure you are on the right track. 



6. If examples of mushrooms, mosses, ferns, lichens, horsetails, and 

 club mosses are available, examine them. Can you tell them apart? How.^ 

 In some cases it may be difficult for you to decide whether or not they 

 are plants without flowers unless you see them at all times of the year. 



7. Divide the class into committees, each of which will report on one 

 of the major divisions of the flowerless plants. Special reports would be 

 made by those who have raised molds or completed other projects. You 

 will then as a class have summarized the text on flowerless plants and you 

 will have made a small beginning toward learning to know the plant 

 kingdom. 



8. Obtain examples of parallel-veined and net-veined leaves. Compare 

 and draw them. You can skeletonize leaves by soaking them in dilute 

 potassium hydroxide. Only the veins will be left. 



9. Examine carefully some dicot flower, such as the sedum or sweet pea 

 or violet. (You will find a description of the flower under plant reproduc- 

 tion. ) Can you identify the parts? Compare with a monocot blossom. 



10. Simmmry. Visit the vegetable market and make a list of the dif- 

 ferent plants seen. Perhaps several students could visit a florist shop and 

 list the flowering plants there. In class, see how many of the plants listed 

 you are able to classify into families. Now if you can sum up briefly 

 what you read about cone bearers, you will have summarized the pages 

 on "The plants with flowers and seeds." 



Further Activities in Biology 



1. Look through the titles of your state publications as well as those 

 of the United States Department of Agriculture for bulletins on mush- 

 room growing. Send for some and report. If you have a cellar with the 

 right conditions you might try raising some. 



2. Ferns are common and easy to press. When carefully mounted they 

 make beautiful specimens. They are relatively easy to identify. 



