But what am I saying? Here comes one now! Such a whirr of wings! Such a dainty bird as poises before the large sweet flower! It thrusts in its bill, but stay! that is not a bird’s bill finding its way to the bottom of those deep-placed nectaries. It is a long, slender tube such as butterflies have, and this is no bird, but a large night-flying moth. These moths are heavier than butterflies and look very much like humming birds when darting through the air. But if you see one at rest you know at once it is no humming bird. When the humming birds are darting about in the sunshine, these moths are hidden beneath a leaf or in some other safe place. Perhaps they fear some bird with a taste for moths will eat them if they come out. Perhaps they love the quiet night. However that may be, as soon as it is dusk they fly out. They are hungry after their sleep through the long summer day, and dart about to find flowers that are still open. The morning-glories, we know, are closed, for they love the bees, but the moonflowers are filling the air with perfume; their fragrance guides the moths to the white flowers that shine out in the dim light. Now you see why the moonflowers are white and why they are fragrant. They wish to call these friendly night-moths to come and carry pollen from flower to flower. If they were red or purple the moths could not so easily see them, and if they had no odor the moths could not smell them a long way off, and so might not come close enough to find them. So our fair Southern friend the moonflower loves the moths and not the bees. Into its long white tube their long, slender tongues can easily reach and find the nectar, and in taking it they brush the pollen against their tongues or their faces, and when they go to another flower it is rubbed against the stigma. The sphinx moths are the fellows with long sucking tubes that fly in the evening. A good many members of the Convolvulus Family make us happy by their beauty, but some of them do more than this. The sweet potato, for instance, gives us something to eat. You know what it gives us, but probably you did not know the sweet potato is a convolvulus and first cousin to the morning-glory and moonflower, and that it has come to us all the way from India. Some say its home is in the East Indies too, and when you go there, if you look in the right place, you may see it growing wild. I doubt if the wild plant bears such big potatoes though; probably they are the result of long cultivation. [Illustration: SWEET POTATO VINE.] It is also said that its home is in tropical America. Very likely it belongs to all these places. Some plants have a way of living all over the world at once. How they managed to get separated so far is a problem we must try to solve some day.