While Uncle George and Frank and Tom were having a game of cricket, Dolly was amusing herself in another way. She had pulled a bunch of daisies and was joining them up into a daisy chain. She finished her daisy chain just as her uncle and the boys finished their game. “We will take some daisies home,” said Uncle George. He stooped down and dug out a whole daisy plant with “First of all,” he said, “I want you to look at the daisy plant. Notice its leaves. Each leaf is broad at the end and narrow where it joins the plant. Notice also that the leaves all form a round green mat on the ground. Now, can you tell me what the leaf resembles in shape.”
“It is like a spoon,” said Tom. “It is,” said his uncle; “and can you see any reason for it being so shaped? “You cannot? Well, I must tell you. All plants whose leaves are all at the ground have leaves shaped something like this. The primrose and cowslip are good examples. We have seen that plants, like the pea, climb up so that their leaves and green parts may Uncle George then drew a circle.
“Now, boys,” he said, “I want you to try to fill that circle with leaves so shaped that they will fill it without covering one another. The best way to do so is to make them broad at the end. If you make them broad at the base and narrow at the end, they overlap and rob each other of light and air. Now you can see why the leaves of the daisy are so shaped. “Take up a daisy and split it down the centre with “There are two distinct kinds of florets,” said Frank, looking at the split daisy with his lens. “Yes,” said Uncle George, “you will see them better if you remove one of each with a pin, and examine them separately.” “The outer florets are very large and white,” said Frank. “They are very flat, while the inner ones are yellow and round. They are very like small crocus flowers. What is that small two-headed thing that comes out in the centre of each floret?” “That is the part which leads to the seed-vessel. Can you see the seed-vessel at the bottom of each floret?” “Yes,” said Tom, “it is large and round. On the top of it and all round the petal part of the floret there are long silky hairs.” “In flowers of this kind, when the seeds are ripe they are carried away by the wind,” said Uncle George. “The petal part withers, but the tuft of hairs remain. They are to the seed what sails are to a ship. They are “Now cut open the seed-vessel and see how many seeds it contains.” “There is only one, I think,” said Frank. “You think correctly,” said his uncle. “Each seed-vessel holds a single seed.” “The seed-vessel in the large white floret is small and flat,” said Tom. “It is,” said Uncle George. “In fact, the outer florets seldom produce seeds.” “Then what is the use of them?” Tom asked. “I’ll show you,” said Uncle George. As he spoke he took up a fresh daisy flower. “Look!” he said, “what a pretty flower it is, with its golden centre and its bright white edge tipped with red. It is like a beautiful star.” Then he pulled off all the large white florets. “Look at it now,” he said. “It is a dingy, ugly little flower. Without its white florets it would not be seen at all. Now perhaps you can tell me what the large white florets are for.” “To help us to see them at a distance,” said Frank. “So that bees and other flying insects may be able to see them,” said Uncle George. “Insects visit flowers for honey, and, in doing so, carry the yellow dust, or pollen, from flower to flower. This pollen, as I told you before, has to do with the making of seeds: and stronger seeds are produced if the pollen comes from another flower. “Now compare a white floret with a yellow one, “Round the stigma—that is the forked tube which leads to the seed-vessel—in the yellow florets, there is a yellow ring of stamens, or pollen-boxes. It is shaped like a little barrel with its ends knocked out, and the stigma grows right up through it. “In the white florets there are no pollen-boxes of any kind. “Thus, we see that the inner florets are perfect florets which produce seeds. “The outer florets have all run to petal. Their business is to show the way to the plain little florets in the middle. “There is another thing about the daisy that I should like you to notice,” Uncle George continued. “If you go out on a dull day, or in the evening, you will find all the daisy flowers closed up. They only open out in bright sunshine, when all the insects are flying about.” Exercises on Lesson VII.
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