CHAPTER IV 



THE CYCLE OF LIFE : FLOWERS 



Questions. 1. Do all kinds of plants produce seeds ? 2. Do all kinds 

 of plants bear flowers ? 3. What is the use of flowers to plants ? 4. How 

 does the odor of a flower help the plant ? 5. How does the odor of a 

 cultivated rose help the plant ? 6. How are seeds made ? 7. Can a plant 

 of one kind produce seeds of a different kind ? 8. Are all bright flowers 

 visited by insects ? 9. Do insects get anything from flowers besides 

 nectar ? 10. Does it hurt plants in any way to remove the flowers ? 



31. Individual life is limited. The life of every individual, 

 plant as v^ell as animal, comes to an end after only a few min- 

 utes, or after many centuries ; dying is a part of being alive. 

 Yet the species, or kind, may continue to live for thousands and 

 thousands of years. New individuals are constantly being pro- 

 duced. The species reproduces itself, although not every living 

 individual can reproduce itself. The term reproduction carries 

 the idea of a special portion being separated from the parent 

 and developing into an individual. Among the more familiar 

 plants, reproduction is by means of seeds. The flower is a 

 special structure related to the making of seeds. 



32. Structure of the flower. In most common flowers, such 

 as wild roses or buttercups, we find certain leaflike parts that 

 attract our notice because of their color. This conspicuous part 

 of the flower is called the corolla, and is commonly surrounded 

 by another set of leaflike parts that make up the calyx, or cup 

 (see Fig. 17). Although this floral envelope (calyx and corolla) 

 is in most plants the first to attract our attention, it is by no 

 means the most important part of the flower. Many species 

 produce seeds without having these organs. 



33. The essential organs. The seeds originate from tiny struc- 

 tures called ovules, which are borne in special organs found at 



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