Part 4

Though the immediate mysteries of the seed and the egg baffle us, yet the most casual lover of God's out-of-doors may hopefully attempt to solve the question of some of the winter homes of insects. Think of the thousands upon thousands of eggs and pupæ which are hidden in every grove; what catacombs of bug mummies yonder log conceals,--mummies whose resurrection will be brought about by the alchemy of thawing sunbeams. Follow out the suggestion hinted at above and place a handkerchief full of frozen mould or decayed wood in a white dish, and the tiny universe which will gradually unfold before you will provide many hours of interest. But remember your responsibilities in so doing, and do not let the tiny plant germs languish and die for want of water, or the feeble, newly-hatched insects perish from cold or lack a bit of scraped meat.

Cocoons are another never-ending source of delight. If you think that there are no unsolved problems of the commonest insect life around us, say why it is that the moths and millers pass the winter wrapped in swaddling clothes of densest textures, roll upon roll of silken coverlets; while our delicate butterflies hang uncovered, suspended only by a single loop of silk, exposed to the cold blast of every northern gale? Why do the caterpillars of our giant moths--the mythologically named Cecropia, Polyphemus, Luna, and Prometheus--show such individuality in the position which they choose for their temporary shrouds? Protection and concealment are the watchwords held to in each case, but how differently they are achieved!

Cecropia--that beauty whose wings, fully six inches across, will flap gracefully through the summer twilight--weaves about himself a half oval mound, along some stem or tree-trunk, and becomes a mere excrescence--the veriest unedible thing a bird may spy. Polyphemus wraps miles of finest silk about his green worm-form (how, even though we watch him do it, we can only guess); weaving in all the surrounding leaves he can reach. This, of course, before the frosts come, but when the leaves at last shrivel, loosen, and their petioles break, it is merely a larger brown nut than usual that falls to the ground, the kernel of which will sprout next June and blossom into the big moth of delicate fawn tints, feathery horned, with those strange isinglass windows in his hind wings.

Luna--the weird, beautiful moon-moth, whose pale green hues and long graceful streamers make us realise how much beauty we miss if we neglect the night life of summer--when clad in her temporary shroud of silk, sometimes falls to the ground, or again the cocoon remains in the tree or bush where it was spun.

But Prometheus, the smallest of the quartet, has a way all his own. The elongated cocoon, looking like a silken finger, is woven about a leaf of sassafras. Even the long stem of the leaf is silk-girdled, and a strong band is looped about the twig to which the leaf is attached. Here, when all the leaves fall, he hangs, the plaything of every breeze, attracting the attention of all the hungry birds. But little does Prometheus care. Sparrows may hover about him and peck in vain; chickadees may clutch the dangling finger and pound with all their tiny might. Prometheus is "bound," indeed, and merely swings the faster, up and down, from side to side.

It is interesting to note that when two Prometheus cocoons, fastened upon their twigs, were suspended in a large cageful of native birds, it took a healthy chickadee just three days of hard pounding and unravelling to force a way through the silken envelopes to the chrysalids within. Such long continued and persistent labour for so comparatively small a morsel of food would not be profitable or even possible out-of-doors in winter. The bird would starve to death while forcing its way through the protecting silk.

These are only four of the many hundreds of cocoons, from the silken shrouds on the topmost branches to the jugnecked chrysalis of a sphinx moth--offering us the riddle of a winter's shelter buried in the cold, dark earth.

Is everything frozen tight? Has Nature's frost mortar cemented every stone in its bed? Then cut off the solid cups of the pitcher plants, and see what insects formed the last meal of these strange growths,--ants, flies, bugs, encased in ice like the fossil insects caught in the amber sap which flowed so many thousands of years ago.

When the fierce northwestern blast Cools sea and land so far and fast, Thou already slumberest deep; Woe and want thou canst outsleep.

Emerson.

CHAMELEONS IN FUR AND FEATHER

The colour of things in nature has been the subject of many volumes and yet it may be truthfully said that no two naturalists are wholly agreed on the interpretation of the countless hues of plants and animals. Some assert that all alleged instances of protective colouring and mimicry are merely the result of accident; while at the opposite swing of the pendulum we find theories, protective and mimetic, for the colours of even the tiny one-celled green plants which cover the bark of trees! Here is abundant opportunity for any observer of living nature to help toward the solution of these problems.

In a battle there are always two sides and at its finish one side always runs away while the other pursues. Thus it is in the wars of nature, only here the timid ones are always ready to flee, while the strong are equally prepared to pursue. It is only by constant vigilance that the little mice can save themselves from disappearing down the throats of their enemies, as under cover of darkness they snatch nervous mouthfuls of grain in the fields,--and hence their gray colour and their large, watchful eyes; but on the other hand, the baby owls in their hollow tree would starve if the parents were never able to swoop down in the darkness and surprise a mouse now and then,--hence the gray plumage and great eyes of the parent owls.

The most convincing proof of the reality of protective coloration is in the change of plumage or fur of some of the wild creatures to suit the season. In the far north, the grouse or ptarmigan, as they are called, do not keep feathers of the same colour the year round, as does our ruffed grouse; but change their dress no fewer than three times. When rocks and moss are buried deep beneath the snow, and a keen-eyed hawk appears, the white-feathered ptarmigan crouches and becomes an inanimate mound. Later in the year, with the increasing warmth, patches of gray and brown earth appear, and simultaneously, as if its feathers were really snowflakes, splashes of brown replace the pure white of the bird's plumage, and equally baffle the eye. Seeing one of these birds by itself, we could readily tell, from the colour of its plumage, the time of year and general aspect of the country from which it came. Its plumage is like a mirror which reflects the snow, the moss, or the lichens in turn. It is, indeed, a feathered chameleon, but with changes of colour taking place more slowly than is the case in the reptile.

We may discover changes somewhat similar, but furry instead of feathery, in the woods about our home. The fiercest of all the animals of our continent still evades the exterminating inroads of man; indeed it often puts his traps to shame, and wages destructive warfare in his very midst. I speak of the weasel,--the least of all his family, and yet, for his size, the most bloodthirsty and widely dreaded little demon of all the countryside. His is a name to conjure with among all the lesser wood-folk; the scent of his passing brings an almost helpless paralysis. And yet in some way he must be handicapped, for his slightly larger cousin, the mink, finds good hunting the year round, clad in a suit of rich brown; while the weasel, at the approach of winter, sheds his summer dress of chocolate hue and dons a pure white fur, a change which would seem to put the poor mice and rabbits at a hopeless disadvantage. Nevertheless the ermine, as he is now called (although wrongly so), seems just able to hold his own, with all his evil slinking motions and bloodthirsty desires; for foxes, owls, and hawks take, in their turn, heavy toll. Nature is ever a repetition of the "House that Jack built";--this is the owl that ate the weasel that killed the mouse, and so on.

The little tail-tips of milady's ermine coat are black; and herein lies an interesting fact in the coloration of the weasel and one that, perhaps, gives a clue to some other hitherto inexplicable spots and markings on the fur, feathers, skin, and scales of wild creatures. Whatever the season, and whatever the colour of the weasel's coat,--brown or white,--the tip of the tail remains always black. This would seem, at first thought, a very bad thing for the little animal. Knowing so little of fear, he never tucks his tail between his legs, and, when shooting across an open expanse of snow, the black tip ever trailing after him would seem to mark him out for destruction by every observing hawk or fox.

But the very opposite is the case as Mr. Witmer Stone so well relates. "If you place a weasel in its winter white on new-fallen snow, in such a position that it casts no shadow, you will find that the black tip of the tail catches your eye and holds it in spite of yourself, so that at a little distance it is very difficult to follow the outline of the rest of the animal. Cover the tip of the tail with snow and you can see the rest of the weasel itself much more clearly; but as long as the black point is in sight, you see that, and that only.

"If a hawk or owl, or any other of the larger hunters of the woodland, were to give chase to a weasel and endeavour to pounce upon it, it would in all probability be the black tip of the tail it would see and strike at, while the weasel, darting ahead, would escape. It may, morever, serve as a guide, enabling the young weasels to follow their parents more readily through grass and brambles.

"One would suppose that this beautiful white fur of winter, literally as white as the snow, might prove a disadvantage at times by making its owner conspicuous when the ground is bare in winter, as it frequently is even in the North; yet though weasels are about more or less by day, you will seldom catch so much as a glimpse of one at such times, though you may hear their sharp chirrup close at hand. Though bold and fearless, they have the power of vanishing instantly, and the slightest alarm sends them to cover. I have seen one standing within reach of my hand in the sunshine on the exposed root of a tree, and while I was staring at it, it vanished like the flame of a candle blown out, without leaving me the slightest clue as to the direction it had taken. All the weasels I have ever seen, either in the woods or open meadows, disappeared in a similar manner."

To add to the completeness of proof that the change from brown to white is for protection,--in the case of the weasel, both to enable it to escape from the fox and to circumvent the rabbit,--the weasels in Florida, where snow is unknown, do not change colour, but remain brown throughout the whole year.

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FEBRUARY

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FEBRUARY FEATHERS

February holes are most interesting places and one never knows what will be found in the next one investigated. It is a good plan, in one's walks in the early fall, to make a mental map of all the auspicious looking trees and holes, and then go the rounds of these in winter--as a hunter follows his line of traps. An old, neglected orchard may seem perfectly barren of life; insects dead, leaves fallen, and sap frozen; but the warm hearts of these venerable trees may shelter much beside the larvæ of boring beetles, and we may reap a winter harvest of which the farmer knows nothing.

Poke a stick into a knothole and stir up the leaves at the bottom of the cavity, and then look in. Two great yellow eyes may greet you, glaring intermittently, and sharp clicks may assail your ears. Reach in with your gloved hand and bring the screech owl out. He will blink in the sunshine, ruffling up his feathers until he is twice his real size. The light partly blinds him, but toss him into the air and he will fly without difficulty and select with ease a secluded perch. The instant he alights a wonderful transformation comes over him. He stiffens, draws himself as high as possible, and compresses his feathers until he seems naught but the slender, broken stump of some bough,--ragged topped (thanks to his "horns"), gray and lichened. It is little short of a miracle how this spluttering, saucer-eyed, feathered cat can melt away into woody fibre before our very eyes.

We quickly understand why in the daytime the little owl is so anxious to hide his form from public view. Although he can see well enough to fly and to perch, yet the bright sunlight on the snow is too dazzling to permit of swift and sure action. All the birds of the winter woods seem to know this and instantly take advantage of it. Sparrows, chickadees, and woodpeckers go nearly wild with excitement when they discover the little owl, hovering about him and occasionally making darts almost in his very face. We can well believe that as the sun sets, after an afternoon of such excitement, they flee in terror, selecting for that night's perch the densest tangle of sweetbrier to be found.

One hollow tree may yield a little gray owl, while from the next we may draw a red one; and the odd thing about this is that this difference in colour does not depend upon age, sex, or season, and no ornithologist can say why it occurs. What can these little fellows find to feed upon these cold nights, when the birds seek the most hidden and sheltered retreats? We might murder the next owl we come across; but would any fact we might discover in his poor stomach repay us for the thought of having needlessly cut short his life, with its pleasures and spring courtships, and the delight he will take in the half a dozen pearls over which he will soon watch?