Part 7

You would hardly think at first glance that it was a relative of the morning-glory. But it is, as you would discover if you looked at it very carefully and saw how much it is like a morning-glory in its way of growing, in spite of appearances.

It comes to us from Mexico, and you could hardly expect a Mexican convolvulus to be just like a South American one, the habits of the two countries are so different, you know.

Why, you would hardly know your own relatives if they had been born and brought up in South America for a few generations.

The next time you go to Mexico be sure and look out for the cypress vine, which, for all I know, may be looked upon as just a common weed there, as we look at thistles and dandelions here. We would think thistles and dandelions beautiful flowers if we had to raise them in gardens with a great deal of trouble. But because we have to dig them out of our gardens and lawns we call them weeds and detest them.

Way down South, and also in some parts of Florida, there lives a lovely convolvulus. It grows something like our morning-glories, only its leaves are all sorts of shapes, heart-shaped and halberd-shaped and angled, all together on the same vine sometimes.

Its blossoms are real flower queens, they are so large and white and fragrant. They have a tube which is three or four inches long, and a snowy border still larger. They are called bona nox, which you know very well is the Latin for “good night.”

The reason they are called this is, they do not open in the morning at all, but always at night.

People have them growing over their porches sometimes, and sometimes call them “moonflowers.”

The long white buds are twisted tightly shut in the daytime, but as soon as the sun sets, if you are watching, you will see something to astonish and delight you. For see, the bud moves a little! Then, all at once, the great white flower spreads out its corolla with a grace and serenity that thrill you. Before your very eyes the bud unfolds, and you have seen a flower blossom out! At the same moment a delicate and delightful fragrance fills the air.

But why does it bloom at night you ask.

The morning-glory has a bright bell to call the bees, but the bees do not fly at night. Does this large, fragrant white flower not care for the bees? Does it not wish pollen from other flowers?

That it does; above all things it wants pollen, and that is why it has opened this large, white, fragrant corolla.

See its tube, how long and deep. What bee could reach into that nectary?

A humming bird might, but the humming birds are all tucked up on their tiny perches sound asleep. They will never sip the nectar from those large white moonflowers.

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.

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.

The sweet potato generally lies flat on the ground and sends out long stems in all directions. Its leaves, as you can see, are more or less like morning-glory and bindweed leaves. Its flowers are also like morning-glories, though they are not so pretty. It has a habit of storing up quantities of starch and sugar in its roots. It does this, hoping to use the starch and sugar again as food in forming new shoots. But sometimes we step in and disarrange all these fine plans, for we, too, need starch and sugar as food, and we take the big sweet roots and eat them.