Kitabı oku: «Moorland Idylls», sayfa 7
XXII.
NESTS AND NO NESTS
Strolling across the moor in the sunshine to-day, past the lonely pine where the night-jar sits crooning to his lady-love in the twilight, I came suddenly across his grey mate herself, and saw her flutter up sleepily in dazed surprise from the bare ground where she was sitting. As she flapped her mottled wings and sailed slowly away, like a blinking owl disturbed in the daytime, I noticed that I had lighted unawares upon her nest, or rather, her eggs, for she lays them on the open, without bed of any sort. I left them untouched, for I am no collector. A few minutes later, I came abreast of the low cliff where the sand-martins have established their twittering colony. The soft yellow sandstone that forms the cutting is honey-combed with their tunnels; and as I leaned on my stick and looked, I saw the busy brown birds gliding in and out, with their long curved flight, and carrying back mouthfuls of gnats and mayflies to their fledgelings in the burrows. It was beautiful to watch them swooping in great arcs over the gorse and bracken, and then darting straight, with unerring accuracy, to the mouth of their tunnels. They alight at the very door with all the skill of born pilots, never missing or overshooting the mark by one inch, but steering upon it so truly that they look as though failure or miscalculation were impossible.
These two little episodes coming together set me thinking; ’tis a bad habit one indulges in when one walks too much alone in the open. In towns one doesn’t think, because the shop-windows, and the horses, and the noise, and the people, and the omnibuses distract one; but in the country, one gives way a great deal too readily to what Plato calls the “divine disease” of thinking. I began to philosophize. How curious, I said to myself, that we have but five kinds of bird in England that hawk on the wing after insects in the open; and of all those five, not one builds a proper respectable nest, woven of twigs and straws, like a sparrow or a robin! Every one of them has some peculiar little fancy of his own – goes in for some individual freak of originality. The night-jar, which is the simplest and earliest in type of the group, lays its eggs on the bare ground, and rises superior in its Spartan simplicity to such petty luxuries as beds and bedding. The swift, that ecclesiologically-minded bird, which loves the chief seats in the synagogue, the highest pinnacles of tower or steeple, gums together a soft nest of floating thistle-down and feathers, by means of a sticky secretion from its own mouth, distilled in the last resort from the juices of insects. The swallow and the house-martin, again, make domed mud huts, and line them inside with soft floating material. Finally, the sand-martin excavates with its bill the soft sandstone of cliffs or roadside cuttings, and strews a bed within for its callow young of cotton-grass and dandelion parachutes.
Why this curious variety among themselves, and this equally curious divergence from the common practice of bird-kind in general? Clearly, thought I, it must bear some definite relation to the habits and manners of the birds which exhibit it. Let me think what it means. Aha, aha, eureka! I have found it! The insect-hawking birds are not a natural group; by descent they have nothing at all to do with one another. Closely as the swift resembles the swallow in form, in flight, in shape of bill, in habits and manners, we now know that the swift is a specialized woodpecker, while the swallow and the martins are specialized sparrows. (I use both words, bien entendu, in quite their widest and most Pickwickian evolutionary acceptation.) The swift and the night-jar belong to one great family of birds; the swallow, the house-martin, and the sand-martin to another. The likeness in form and in mode of flight has been brought about by similarity in their style of living. Two different birds of two different types both took, ages since, to hawking after flies and midges in the open air. Each group was thus compelled to acquire long and powerful wings, a light and airy body, a good steering tail, a wide gape of mouth, and a rapid curved flight, so as to swoop down upon and catch its petty prey unsuspected. So, in the long run, the two types which hawk most in the open, the swifts and the swallows, have grown so like that only by minute anatomical differences can we refer the remoter ancestry of one species to the woodpeckers and humming-birds, and the remoter ancestry of the other to the tits and sparrows.
How does their manner of life affect their mode of nesting, however? Indirectly, in this way. Birds that live largely off seeds and fruits and hard-shelled beetles, have hard short beaks to grind their food with, and sit much in thickets, scrub, or hedgerows. But birds that hawk on the wing after small soft flies must have wide soft bills, and a gaping mouth; they can hardly perch at all on trees or bushes, and their feet are too weak to be of much use for walking. Indeed, if a swift once alights on the ground, he can scarcely get up again, so difficult is it for the long wings to work in a narrow space, and so slight a power of jumping have the feeble little legs. Hence it follows that birds of the hedgerow type can readily build nests of twigs and straws, which they gather as they perch, or seek on the ground; and they are enabled to weave them with their hard bills and active feet; while birds of the hawking type cannot pick up sticks or gather straws on the ground, and have beaks quite unadapted for dealing with such intractable materials. The consequence is they have been compelled to find out each some new plan for itself, and to build their nest out of such stray material as their habits permit them.
The night-jar, a stranded nocturnal bird of early type, with very few modern improvements and additions, solves the problem in the easiest and rudest way by simply going without a nest at all, and laying her eggs unprotected in the open. Nocturnal creatures, indeed, are, to a great extent, the losers in the struggle for existence; they always retain many early and uncivilized ways, if I may speak metaphorically. They are the analogues of the street arabs who sleep in Trafalgar Square under shelter of a newspaper. The sand-martin, an earlier type than the swallow or the house-martin, burrows in sandstone cliffs, which are pre-human features, though man’s roads and railways have largely extended his field of enterprise. But the house-martin and the swallow, later and far more civilized developments, have learned to take advantage of our barns and houses; they nest under the eaves; and being largely water-haunters, skimming lightly over the surface of ponds and lakes, they have naturally taken advantage of the mud at the edges as a convenient building material. Last of all, the soaring swift, the most absolutely aërial type of the entire group, unable to alight on the ground at all, has acquired the habit of catching cottony seeds, and thistle-down, and floating feathers in his mouth as he flies, and gumming them together into a mucilaginous nest with his own saliva. The Oriental sea-swifts have no chance of finding even such flying materials among their caves and cliffs, and they have consequently been driven into erecting nests entirely of their own inspissated saliva, without any basis of down or feathers. These are the famous edible birds’-nests of the Chinese; they look like gelatine, and they make excellent soup, somewhat thick and gummy.
XXIII.
THE CROUCH OAK
The old Crouch Oak on Walford Green is one of the sights of Surrey. It raises its gnarled and hollow trunk in the centre of the Ploy-Field, an ancient common meadow, and though decayed in its heart, is reckoned still among the principal bounds of Ringmer Forest. Its girth at the height of a man’s arms is over twenty feet. Beneath its spreading branches stands an upright stone of immemorial antiquity, which only the righteous wrath of a local archæologist succeeded in preserving a few years since from the modern desecration of a Jubilee inscription. This close combination of sacred tree and sacred stone is frequent and significant; it occurs all the world over, from Britain to the New Hebrides; it is found in India, in Syria, in Germany, in Ceylon, in civilized Rome, in barbaric New Guinea. Wherever the sacred tree spreads its brooding circle of welcome shade, there under its huge boughs the sacred stone bears witness to antique or still surviving rites of human sacrifice.
It is this, indeed, that gives our British Gospel Oaks their unique interest amid the public monuments of England. Alone among the temples of our old heathen faith they have outlived the overwhelming deluge of Christianity. In the south of Europe we have still the Parthenon and the columns of Pæstum to testify boldly to the older creeds. In the north, where temples made with hands were rarer, where art had not learned to raise such colossal piles as Karnak or Denderah, the sacred oak alone remains to us now as a lingering memorial of the cult of our ancestors. Even these, too, have been Christianized, in accordance with Gregory’s well-known advice to Augustine. The holy sites of the ancient faiths, said the wise Pope, in his epistle, were still to be respected; but the demons who inhabited them were to be exorcised by the use of Christian symbols, and the temples were to be sanctified to Christian worship. In accordance with this policy, a figure of the cross was marked upon the bark of the old sacred tree in Walford Ploy-Field, which thus became known as the Crouch or Cross Oak; for the Latin crux came first into our language under the truer English form of crouch, and only assumed its later pronunciation of cross under northern influences. Similar Christianization of holy oaks, shire oaks, boundary oaks, Druid oaks, and other heathen temples or heathen termini, went on all over England; so that what were once Thunor’s trees and Woden’s trees, or still earlier, the sacred haunts of native Celtic deities, became in the end those “Gospel Oaks,” under which, at the annual beating of the bounds, the priest stopped with his acolytes to read a few verses of St. Luke or St. Matthew. Sometimes, indeed, hardly more than the memory of some particular episode in the history of the sacred tree now survives, as at Addlestone, near Chertsey, where there is also a crouch oak, chiefly famous at present from a local tradition that Wickliffe once preached under its canopy of branches. But the older holy and even phallic virtue of this sacred trunk is proved by the fact that decoctions of its bark taken internally, after a well-known and almost world-wide fashion, are still considered by the girls of the village to operate as a love-charm.
The history of these ancient trees, so far as we can reconstruct it from the piecemeal evidence, is picturesque and singular. Originally, I believe, they were planted as saplings over the barrow or tumulus of some barbaric chieftain; not a few of them, indeed – like the King’s Oak at Tilford, near Farnham – still retain some title which recalls their royal or funereal origin. The sacred stone, which in every case seems once to have stood under their dense shade, was doubtless at first the standing-stone or gravestone of the buried chief; though later it probably served as an unhewn altar for the village sacrifices, like that offering of the lamb which till recent years was still torn to pieces on an anniversary festival in the Ploy-Field at Holne, in Devonshire. Every year, in point of fact, the people of each village used once to perambulate their bounds, as at the Roman Terminalia, and offer up at each holy tree and each terminus stone, which formed the main landmarks, a human sacrifice. The victims were usually boys – most probably captives from neighbouring tribes or villages; failing that, they were “bought with a price” within the tribe itself from their unnatural parents. Traces of these customs survive all the world over, while the practice itself is closely bound up with the worship of Terminus and other boundary spirits. In later and milder days, however, though the habit of beating the bounds survived, the incidents that accompanied it were considerably mitigated. The ceremony at first was essentially an exorcism, or driving of evil spirits beyond the village limits; and the boys seem to have been slaughtered as boundary guardians, in order that their ghosts might protect and maintain the local frontier. They were also scourged before being put to death, after a common superstition, so that their tears might act as a sympathetic rain-charm. But in later Christian days it began to be felt that to read the Gospels under the sacred oak of the boundary would sufficiently drive away all evil influences; and though the boys were still beaten at each terminus as a rain-charm, the meaning of the incident was so wholly forgotten that it was commonly interpreted as a means of impressing the boundaries on their memories – a foolish gloss of the usual fatuous eighteenth-century rationalizing type. Thus the Gospel Oak at Cheriton is now only remembered as the tree under which the Gospel was read at the perambulation of the bounds; the Crouch Oak at Addlestone has sunk into a prosaic legal boundary-mark of Windsor Forest; and the Twelve Apostles at Burley, near Ringwood, now reduced to five, have been finally Christianized out of all recognition, so that I cannot even conjecturally reconstruct their original dedication to some ancient Celtic or Teutonic deities.
XXIV.
A SPOTTED ORCHIS
Like Mr. Chamberlain, I too am an orchid-grower. I own three acres (without a cow) on a heather-clad hilltop, and no small proportion of that landed estate is “down under orchids.” Not that I mean to say the species I cultivate, or rather allow to grow wild, on my wild little plot would excite the envy of the magnate of Highbury. They are nothing more than common English spotted orchids, springing free and spontaneous among the gorse and heather. But, oh! how beautiful they are! how much more beautiful than the dendrobiums and cattleyas, the flowering spiders and blossoming lizards of the rich man’s hothouse! How proudly they raise their tall spikes of pale bloom, true sultanas of the moorland! how daintily they woo the big burly bumble bees! how gracefully they bend their nodding heads before the bold south-west that careers across the country! They seem to me always such great regal flowers, yet simple with the simplicity of the untrodden upland.
Take a spike and look at it close; or, better still, grub it up by the roots with the point of your umbrella, and examine it all through from its foundation upward. It springs from two tubers, not unlike a pair of new potatoes to look at, but deeply divided below into finger-like processes. Those divisions it was that gave the plant its quaint old English title of “dead men’s fingers” – for, indeed, there is something clammy and corpse-like about the feel of the tubers; while that “coarser name” to which Shakespeare alludes in passing, is due to their general shape, and is still enshrined in the Greek word “orchid” which everybody now applies to them without thinking for a moment of its unsavoury meaning. But the two tubers are not of the same age. One is old and wilted; the other is young and fresh, and, as the advertisements say, “still growing.” The first is last year’s reserve-fund for this year’s flowering stem; the second is this year’s storehouse of food for next year’s blossom. Thus each season depends for its flowers upon the previous year’s income; the leaves, which are the mouths and stomachs of the plants, lay by material in due season; and the spike of bells proceeds from the tubers or consolidated reserve-fund as soon as the summer is sufficiently advanced for the process of flowering. Few plants with handsome heads or trusses of bloom, indeed, can afford to produce them upon the current season’s income; therefore you will find that most large-flowered forms, like lilies, tulips, hyacinths, and daffodils, if they wish to blossom early in the year, depend for their food-supply upon a bulb or tuber of last season’s making. Only in the orchids, however, do you find this curious device of a pair of tubers at once side by side, one being filled and fed, while the other is being slowly devoured and depleted. By the end of the season the new tuber is rich and full to bursting, while the old one is withered, flaccid, and empty.
From the tuber, in early spring, start the pretty lance-shaped leaves – green, dappled with leopard spots of some deep brown pigment. The use and meaning of these beautiful spots on the glossy green foliage no one has yet deciphered; it remains as one of the ten thousand insoluble mysteries of plant existence. That is always so in life. We tell what we know; but what we know not, who shall count it or number it? Yet the flowers, after all, are the true centre of interest in the English orchid. Thirty of them in a spike, pale lilac or white, all starred and brocaded with strange flecks of purple, they rank among the most marvellous of our native flowers in shape and structure. The long spur at the back is the factory and reservoir for the abundant honey. The face of the blossom consists of a broad and showy lip, the flaunting advertisement to bee or butterfly of the sweets within; it is flanked by two slender spreading wings, above which a third sepal arches over the helmet-like petals. Beneath this hood, or dome, in the centre of the column, the club-shaped pollen-masses lie half concealed in two pockets, or pouches – dainty little purses, as it were, like fairy wallets – slit open in front for the bee’s convenience. The base of the pollen-masses is sticky or gummy; and they are so arranged, of set purpose, in their pouches, that the moment the bee’s head touches them, they cling to it automatically, by their gummy end, and are carried off without his knowledge or consent to the next flower he visits. But if you want to see exactly how this pretty little drama of plant life is enacted, you need not wait, as I have often done, silent on the heath for half an hour together, till some blustering bumble bee bustles in, all importance. It suffices for demonstration just to pick a spike and insert into the mouth of the honey-spur a stem of grass, which does duty for the bee’s head and proboscis, when straightway “the figures will act,” as they say on the penny-in-the-slot machines, and the pollen-masses will gum themselves by automatic action to the imaginary insect.
The reason for this curious and highly advanced device is that orchids are among the plants most absolutely specialized for insect-fertilization. Most species of orchid, in fact, can never set their seeds at all without the intervention of these flying “marriage priests,” as Darwin quaintly called them. If left to themselves, the flowers must wither on their virgin thorn unwed, and no seed be set in the twisted ovary. But when the bee goes to them in search of honey, the pollen-masses gum themselves to the front of his head, though just at first they point upward and inward. Then, after a short time, as he flies through the air, they contract in drying, and so point forward, in the direction in which he will enter the next flower he visits. This brings the pollen directly into contact with the sensitive cushion or pad of the ovary in the flower so visited, and thus results in the desired cross-fertilization. For the ovary, too, is gummy, to make the pollen stick to it.
A roundabout way, you think, to arrive, after all, at so simple a conclusion? Well, that is the habit of Nature. And again, bethink you, good, easy-going human being, how great are the difficulties she has to contend with, especially in the case of the plant creation. Put yourself in the orchid’s place, and you will see the reason. For remember how absolutely fixed and limited are plants, each rooted to the soil in a single small spot, each tied by strict conditions of rock, and water-supply, and air, and wind, and sun, and climate, from which none can escape, try they all their hardest. The opposite sides of a road are to them as the two poles, one with a sunny and southward-looking bank, the other with a cold and forbidding northern aspect; so that what flourishes apace on the first would shiver and die of chill winds on the second. Remember, too, that, save in the mildest degree, plants have no power of spontaneous or independent movement; they cannot stir from their birthplace, were it but for a single inch, nor move their own limbs save as the wind may sway them. Creatures thus narrowly and inevitably bound down must needs take advantage of the power of movement in all other kinds, wherever it will benefit them. Hence the use plants make of insects as common carriers of pollen; the use they make of birds as dispersers of seeds; the use they make of natural agencies, such as wind or stream, to waft winged thistle-down, to carry the parachutes of the dandelion and the willow, or to float the male blossoms of such water-weeds as vallisneria. Behold! I show you a mystery. The secret of the whole thing is that plants, being fixed themselves, must needs employ birds and insects as their Pickford vans – must rely on wind or stream for such casual services as wind or stream can easily afford them. Only in a few species can they effect anything like active movement for themselves, as one sees in the rooting runners of strawberries, or the wandering tubers of certain vagrant orchids, which spread far afield from last season’s nesting-place. These are clever devices for securing fresh virgin soil – “rotation of crops,” as the farmers put it.
