I T was moonlight on Holiday Hill. The light was bright for night-time, as the moon was full. By it could be seen a well worn path that led up one side of the hill.
The odors of flowers drifted across the slope, some of them far sweeter than they ever were by day.
A quivery, quavery sound came through the quiet air. Somewhere out in the night an owl was calling—or perhaps it was a raccoon. The voices of some owls are so much like those of raccoons that it is often hard to tell the difference.
Moonlight, fragrance, strange musical notes—all seemed like invitations to pleasant and interesting experiences that can never be met during daytime hours. Anyone accepting them could have something better than dreams to remember by following the beaten track that lay between the meadow and the old hedgerow.
Holiday Hill by moonlight
The plants beside the path had strange night manners. Clovers had folded their leaves. Dandelions had hidden their golden heads. They seemed to be resting. Bees and butterflies that sought flowers during the sunny hours were not there at night. They, too, were resting. Indeed, the whole daytime world seemed to be asleep.
But the night creatures were awake. There was a sound of some small animal moving among the bushes in the hedgerow. Several bats were flying overhead. A little owl drifted by on silent wings. A moment later he gave a sweet shivery call. Another owl answered him from a distance.
Even children who went often up the hill in the daytime, and were most familiar with it then, would have stopped in amazement halfway up the sloping path. For in the summer night, the trail led to a world of strange surprises.
A wave of fragrance passed across it—a scent sweeter than any the day breezes ever brought the place. And all around were wide-flaring flowers. They were on tall plants that, during the day, looked like big wilty weeds slouching in the sunshine.
But now these evening primroses were at their loveliest. Their stalks stood alert. Their dew-drenched leaves were fresh. Their pale yellow petals opened into blossoms that were marvelously beautiful.
Suddenly there was a whirring sound of wings as if a humming bird had come. And there, hovering before the very nearest flowers was a creature about the size and somewhat the shape of a humming bird. Like a humming bird, too, it poised before one flower and then another to sip the nectar it found.
Of course a humming bird would have been asleep. This was not a bird of any sort. It was a beautiful insect named, because of its appearance, a humming-bird moth.
A humming-bird moth
The wide-open, gleaming blossoms and the heavy fragrance of the evening primroses might seem strange and wonderful to a human being who usually walked that path in the daytime. But they did not surprise the moth. The light and odor of these flowers were a part of the life of the large insect. It, and others of its kind, visited evening primroses every pleasant night at this season of the year.
The large bird-shaped insect drank nectar and departed. A second visitor, however, stayed with the plants. She was a moth, also, though a small one with fringes on her wings. She was, indeed, so very, very small that a good name for her is Tiny. This wee mother had an important errand that night. She had some eggs to lay and she must put them in just the right places.
The baby caterpillars that were going to hatch from those eggs would need a special sort of diet. They would have such dainty appetites that nothing would agree with them except the tender parts that are found inside the buds of evening primroses. So, of course, the mother moth placed her eggs near the favorite food of her young. That was all she could ever do for them.
She is likely to be far away before it is time for one of her caterpillar brood to hatch. The young larva, however, does not need to find its mother. It makes itself comfortable inside a bud and feasts on stamens with lobes of stigma for a side-dish.
Now, as you know, plants grow stigmas and stamens for purposes of their own. That is their normal way of providing for the seed-children. So a primrose bud that has had its most important parts nibbled out may quite as well not waste its energy in blossoming.
But the fluids of growth pour into such a bud as they do into the others that are whole and sound. The bud responds—not by opening its petals and being a flower, but by staying closed and growing fat and chunky until it is just the sort of cozy nursery to hold a young caterpillar.
So, when you look at a bud of an evening primrose, you can tell by its shape whether a caterpillar has been living inside it. If the bud is long and slender, it should open some evening into a beautiful and fragrant flower. But if it is short and plump, a blossom will never come out of it though something else may.
For there will be a time when the little rascal inside has eaten its fill and must leave. It chews a round doorway through the side of the bud for its escape. Next it spins a filmy cocoon of silk. Within this dainty sleeping bag it changes first to a pupa. A fortnight or so later the pupa, in turn, changes to a sprite of a fringe-winged moth like Tiny, its mother.
A moth of a third kind often visits the evening primrose. Her first name is rather long; but her second name is Florida, so we will call her that. Florida's beautiful wings measure a little less than an inch and a quarter across when they are spread wide open. They are pink with pale yellow borders. Like the big humming-bird moth, this lovely creature seeks the blossoms to drink sweet nectar. Like Tiny, with the fringy wings, she comes to lay her eggs.
The young caterpillars which hatch from her eggs are green. At first they nibble holes in the tender buds. When they are older, they cling to the unripe seed-pods, the color of which matches the green of their bodies.
During the day the caterpillars rest among the seed pods so quietly that even keen-eyed and hungry birds may not notice them, although they are in plain sight. But when night comes they are awake and active. They bite into the juicy pods filled with seeds that seem as tempting to their taste as green peas are to ours. Before morning comes they have eaten so much that they can rest all day without being too hungry.
Florida, the mother with the rosy and yellow wings, sips nectar from dusk to dawn or busies herself during the night with her eggs that need to be laid. She, also, hides on the plant while she takes her daytime nap. She does not stay among the seed pods with her green caterpillar family, however. She seeks a nook more in harmony with her own colors.
The primrose flowers that were open a night or two before hang with drooping petals in the sunlight. The yellow blossoms, in fading, have become somewhat pinkish inside. The sleepy moth creeps into one of these chambers, pink-lined and yellow-edged. The yellow borders of her pink wings reach a little beyond the petal tips.
If you think Florida will be easy to find when she is napping, go and hunt for her some day!
Fortunately for evening primroses, they have so many seeds that some can be spared to the hungry caterpillars that will grow to be lovely moths. There will be seeds for birds to eat, too, and even then there will be enough left to be scattered on the ground by the winds.
A plant that sprouts from one of these seeds does not grow to be tall during its first season. It spends that time spreading a rosette of leaves flat on the ground.
All the soil under this round mat belongs to the seedling primrose. That is the way it has of claiming its own home. Other plants cannot thrive in the shade under the thick leaves; and so the primrose has room for its own roots.
Over-wintering rosette of evening primrose
The young plant passes its first winter as a circular tuft of leaves. In the spring it is ready to send up a tall central stem. When summer comes this is tipped with yellow flowers most fragrant and lovely at night.
Although evening primroses grow near the tops of rather high hills, they grow also in low places. They are so common that you cannot go far in most country places without passing some of them.
Perhaps you have seen them only on some sunshiny day when their stems seemed weak, their leaves were limp, and their flowers were drooping. It may be that even their scent was stale and feeble. But it is not fair to judge an evening primrose by the way it looks in the daytime.
Evening primroses, of course, should be visited at night, as you can tell by their name. It is not necessary to wait until very late, however. The two pictures below were both taken of the same plant one evening shortly after eight o'clock. The second photograph was taken ten minutes later than the first. Who would not like to see so many petals fly open in ten minutes?
Only one flower was open at five minutes after eight
Seven flowers were open at fifteen minutes after eight
It was Margaret Deland who told how children came
To watch the primrose blow. Silent they stood,
Hand clasped in hand, in breathless hush around,
And saw her shyly doff her soft green hood
And blossom—with a silken burst of sound.
And John Keats knew, too,
A tuft of evening primroses
O'er which the wind may hover till it dozes;
O'er which it well might take a pleasant sleep,
But that 'tis ever startled by the leap
Of buds into ripe flowers.
Surely with the speech of poets in our ears, it would be unbecoming of me to tell you in prose how these blossoms open.
After all, why should you be told? For those of you who live anywhere from Labrador to the Gulf of Mexico and east of the Rocky Mountains are likely to be near enough a wild plant of this sort to go and see for yourselves how it is done. Those who dwell in other places can, perhaps, visit a garden variety which will serve the purpose as well.