How pollen is carried from one flower to another.If a branch of a pine or oak tree or a piece of ragweed or a corn tassel is shaken slightly at the time the pollen is ripe, the pollen, in the form of a light, dry dust, will fall out in great quantities.How do you suppose pollen of these flowers may be carried from one flower to another?Explain the reason for the enormous quantity of pollen produced.The stigmas of flowers pollinated in this way are frequently very much enlarged and branched so as to expose a large surface.What is the advantage of this?These flowers that are pollinated by the wind do not correspond in their appearence to our idea of flowers.They are usually greenish and inconspicuous with no odor or bright colors.Many flowers have pollen which is not so dry and light as that of the flowers we have been considering.They evidently cannot have pollen carried to any extent by the wind.These are our familiar flowere and of various colors and frequently having more of less odor.You will recall that you have seen insects, eespecially bees and butterflies, visiting them.The insects are seeking the sweet material, nectar, which is down in the interior of the flowers.By pulling out the little flowers from a head of red clover, and touching their bases with the tongue, you can taste the nectar.Examination of the head of a butterfly and the legs and body of a bee will show you that they are covered with hairs.Explain now how you believe these flowers are pollinated.

The irregular shapes of flowers are in general associated with making more certain that the proper kinds of insects will visit them; and the stamens and pistils are so arranged that the insect is quite certain to rub against them to receive pollen from one flower, and then to rub the pollen off on the stigma of the next flower visited.

Some flowers have their pollen carried by water; and in some cases humming birds act as the carriers ; but the great majority of flowers are pollinated either by wind or by in- sects.Insect-pollinated flowers have much less pollen than wind-pollinated flowers.Explain.

Nearly all of the flowers that bloom at night are white or yellow.What reason can you give for this?Flowers have various means of excluding small crawling insects like ants.Of what advantage is this to the plant?