The path up from the Llyn to the crest of Mynydd Mawr leads for some distance along the mossy, boulder-strewn course of a mountain torrent, which takes its rise in a fairy spring close below the actual summit of the craggy peak. It is a stiff pull for fair-weather pedestrians, this almost untrodden tourist trackway, with here and there a hand-and-knee clamber over great glacier-marked bosses of solid granite; but the exquisite glimpses we get at every fresh spur over the bare shoulders of Moel Siabod and into the cleft valley of the upper Conway more than compensate for the rough stony walking and the obvious damage to one’s nether integuments. Very few casual beaten-road visitors ever find out these lonely footpaths up the less-frequented mountains; the mass takes its circular tour round the regulation road by Llanberis, Beddgelert, and Capel Curig, leaving Mynydd Mawr and its neighbouring Carnedds out in the cool shade of popular neglect. So much the better for those wandering naturalists who love to ramble among unhackneyed scenes, and to spy out wild nature in all her native loveliness, an Artemis who only bares her beauty among the deepest and most secret recesses of glade or woodland.
Fig. 41. — Lloydia serotina
(Mountain Tulip).
Here by the bank of the tiny torrent, where I shall stop and rest on a smooth stretch of naked rock for a few idle minutes, there is beauty enough in all conscience to charm the spellbound eyes of any intrusive Actæon. The moist fissures of the water-worn granite are richly clad with filmy fronds of alpine ferns; the drier crevices among the tumbled rocks are tufted with the black stems and graceful foliage of the maidenhair spleenwort; and the scanty alluvial mould on the slopes beyond is carpeted by lithe creeping sprays of beautiful branching club-moss. All around me, a wealth of luxuriant mountain vegetation covers the peaty soil of the hollows, or the shallow granitic clay washed down into the crannies from the weathering crags above. There are insect-eating sundews, with their clammy red-haired leaves inclosing the half-digested bodies of a dozen tiny flies, whose attention they have falsely attracted with their delusive show of pretended honey. There are equally deceptive butterworts, with tall scapes of bright blue blossoms, and with pale yellowish-green foliage curled tightly round their mouldering victims in a deadly embrace. There are Alpine saxifrages, unfolding their pretty pinky-white flowers to the eager advances of the fertilising bees. And here amongst them all, in a sheltered nook of the inclosing granite débris, is the great prize of the day, the wee slender mountain tulip, in search of which I have come out this breezy morning, and whose actual home on the side of Mynydd I hardly expected to light upon so easily or so quickly in the upward march.
Of course I was told beforehand exactly where to look for it by the torrent’s brink; for our botanists have long ago so thoroughly overhauled every inch of England, Scotland, Wales, and Ireland, in search of specimens, that every individual station for every rare British plant is perfectly well known to them, and printed in minute detail in half a dozen British floras. But I feared that here our little mountain tulip might be quite extinct already, exterminated by the too pressing attention of its numerous dilettante admirers; for as soon as your average collector finds a last lingering relic of some moribund British race on down or moorland, his first notion is to complete its destruction by rooting up the one remaining individual as a unique specimen, to become a permanent record of his luck and skill in the brown paper treasuries of his own herbarium. We, however, are naturalists of another kidney, I trust: we will observe and examine our little treasure carefully on the spot, but we will not pull it up ruthlessly, bulb and all, or press its pretty blossoms under a dead weight of books and drying paper, in order to preserve its miserable mummy in the wretched cemetery of a hortus siccus. Long may it flourish on its native hill-side, and may no scientific hand ever grub it up as the cruel trophy of a specimen-slaughtering raid! Indeed, to be perfectly frank, like the canny Scot who was ‘no thot sure of Jocky,’ I have not trusted even my readers themselves with the exact secret of my tulip’s whereabouts. I will confess that I have invented the name of Mynydd Mawr on purpose to deceive, and I have led up to the summit by a roundabout path through the glen of Conway in order to prevent any future intruder from retracing his steps without me, and annexing for his own private aggrandisement the pretty flower whose life I have so chivalrously and humanely spared. When we come to learn the history of its race, I feel sure every one will sympathise in the sentiment which makes me wish to preserve this solitary colony of Alpine flowers as long as possible from the desecrating hands of the abandoned plant-collector.
First, let us look exactly what manner of lily it really is, and then we will go on to unravel together the clues and tokens of its romantic history. See, it is a little simple grass-like plant, sending forth from its buried bulb two or three very slender blades by way of leaves; and from their midst springs a graceful bending stem, surmounted by a single star-shaped white blossom. At least, it looks white at first sight, though when you come to examine it more closely you can observe three red lines running down the face of each petal, and converging on a small bright golden spot at their base. Those lines are in fact honey-guides for the mountain insects, pointing them the shortest road to the sweets stored up in the nectaries, and so saving them any extra trouble in looking about for their morning’s meal. On the other hand, the insects repay the flower for its honey by carrying pollen from blossom to blossom, and so enabling the plant to set its seed. Of course, unless the young capsule in the centre of each blossom is thus fertilised by pollen from one of its neighbours, it never ripens into a seed-bearing fruit at all; and, indeed, in the economy of the plant itself, the sole object of the blossom, with its bright petals, its store of honey, and its faint perfume (almost imperceptible to any save very delicate senses), is simply to induce the bee or the butterfly thus to convey the fertilising powder from one head of flowers to another of the same sort.
Our little plant has of course a botanical name of the usual clumsy kind; but in this particular instance there is a certain rough fitness in its application, for being a Welsh lily by nature it is duly known by a Latinised Welsh name as Lloydia. Now, I am not going this morning to inquire fully into the whole past history of the original family from which it springs — that would be too long a subject for an off-hand lecture as I sit here basking on the bare granite slope; I propose only entering in any detail into the last chapter of its chequered career, and asking how it has managed to keep its foothold for so many ages in this one spot and on a few neighbouring Snowdonian summits. But before we go into that final question we must just begin, by way of preparatory exercise, with a very brief account of its earlier origin. Lloydia serotina, then, to give it the full benefit of its Latinised name, is a mountain plant of northern and Arctic Europe, as well as of the chillier portions of Siberia and British North America. Further south, it is found only in the colder upland shoulders of the Alps, the Caucasus, and the Altai range, as well as in a few other great snowy mountain systems; but in Britain it occurs nowhere except on one or two of the higher mountains here in North Wales. By origin, it is a very early and simple offshoot of the great lily tribe; one of the most primitive lilies, indeed, now existing on the face of the earth. Like all others of that vast family, it has six petals and six stamens or pollen-bearing sacs; but it still retains a very early form of lily flower in its open star-shaped blossom as well as in one or two other smaller peculiarities. The cultivated tulips of our gardens, varieties of a wild Levantine species, are all descended from a somewhat similar form; but with them the course of development has gone much further; the petals have grown far larger and more conspicuous, in order to allure the eyes of bigger southern insects, and the general form of the flower has become bell-shaped instead of star-shaped, in order to ensure more safe and certain fertilisation by these winged allies; for in a tubular blossom the pollen is much more likely to be brushed off from the insect’s head on to the proper portion of the unripe capsule than in an open spreading flower like our Lloydia here. Hence we may fairly say that Lloydia represents an early ancestral form from which the modern and more southerly tulips are nature’s enlarged and improved varieties.
But how did these pretty little white lilies get here, and why do they still remain here in their early simple form, while their southern sisters elsewhere have been slowly modified into brilliant yellow bell-shaped tulips? Thereby hangs a most curious and delightful tale. For I have very little doubt that the ancestors of our pretty lilies here have been growing uninterruptedly in the present spot for many thousands of years, and that during all that time they have gone on reproducing themselves by seed from time to time, without once having crossed their stock with any of their congeners in the Arctic regions or in the great snow-clad ranges of central Europe. Indeed, I very much doubt whether they have ever even intermarried with their neighbours on the other Snowdonian summits, for I think I shall be able to show good reasons for believing that each of these little isolated colonies has lived on for ages all by itself on each of their three scattered peaks in the North Welsh district.
It is a curious fact, certainly, that one should find a single species of Arctic flower reappearing at such long distances in such isolated spots under closely similar circumstances. If we go to the great snow-clad stretches of land which extend around the Arctic Circle in Europe, Asia, and America, we shall everywhere find our little lily growing in abundance close up to the line of perpetual snow, though its diverse habitats are there divided by wide expanses of open sea. If, again, we cross the whole of the German plains, we shall see no Lloydias in the intervening tract; but when we reach the Alps and the Pyrenees, we shall a second time come upon other isolated colonies of the self-same flower. Once more, we may turn eastward, and we shall meet with it, after a long march, among the Carpathians and the Caucasus; or we may turn westward, and then we shall light upon it again on the craggy sides of a few solitary Welsh mountains. How does it come that in every cold tract we find the self-same species recurring again and again wherever the circumstances are fitted for its growth? and how have its seeds or bulbs been conveyed across such wide stretches of intervening sea or valley to so many distinct and separate chilly regions?
One obvious answer might be, that under similar conditions a like flower had everywhere been developed from some common plant of lowland or temperate districts. But in reality such absolute similarity of independent development never actually occurs in nature, for the various Lloydias are not merely rather like one another, but are actually one and the same species, as like each other (to quote our old Welsh friend Fluellin) ‘as my fingers is to my fingers.’ Now, naturalists know that such absolute identity of structure can only arise through unbroken descent from a common origin; wherever two species are separately descended from unlike ancestors, however close their analogies may be, they are always at once marked off from one another by some very obvious points of structural dissimilarity. Nor can we suppose that the seeds of the Lloydia have been transported from one place to another by mere accident, clinging to the legs of Arctic birds, or carried unwittingly on the muddy heels of globe-trotting tourists. Such accidents do indeed occasionally occur, and they account for the very fragmentary manner in which remote Oceanic islands like the Azores or St. Helena are peopled by waifs and strays from the fauna and flora of all neighbouring continents. But as we have already seen in the converse case of the hairy spurge, it would be incredible that such an accident should have occurred over and over again in a hundred separate cases, so that every suitable place in the whole northern hemisphere should separately, by mere luck, have received a distinct colony of appropriate cold-climate plants. Incredible, I should say, even if the instance of the Lloydia stood alone without any analogues; but in fact, as I shall try to point out by-and-by, it is only one instance out of a thousand that might be quoted; for every Arctic land and every snow-clad Alpine peak is covered close up to the limit of vegetation with dozens or hundreds of similar plants, insects, and animals, which are nowhere found in all the intervening temperate or lowland regions. Clearly all these coincidences cannot be due to mere accident; we must seek for their reason in some single and common fact.
See this great rounded block of smooth granite on whose solid shoulders I am now sitting; how wonderfully grooved and polished it is, with long, deep, rounded furrows running lengthwise across its face in the same direction as the general dip of the Conway valley. What can have made those curious parallel channels on its naked surface, I wonder? Any one who has ever looked closely at the rocks about the foot of a glacier in Switzerland will recognise at once what was the agency at work on the granite slopes of Mynydd Mawr. Those are most undoubtedly ice-marks, caused by the long, slow, grinding action of the superincumbent glaciers. For of course everybody knows nowadays that there was once a time when great glacial sheets spread over the combes and glens of Snowdonia, as they spread to-day over the nants of Chamounix and the buried basin of the Mer de Glace.
Dr. Croll’s calculations have shown that the astronomical conjunction necessary for the production of such a state of things must have occurred some two hundred thousand years since; and from that date down to eighty thousand years ago our planet kept presenting alternately either pole to the sun during long cycles of 10,500 years each; so that, first, the northern hemisphere enjoyed a long summer, while the southern was enveloped for a vast distance from the Antarctic Circle in a single covering sheet of ice; and then again the southern hemisphere had its lengthened spell of tropical weather, while the north was turned into one enormous Greenland down as far as the British Isles. Eighty thousand years ago, or thereabouts, this condition of things began to change; the climate of the north became more genial; and ever since that date our sober planet has oscillated within gentler limits, producing only such alternate results of annual summer and winter as those with which we ourselves are now familiar.
When the glaciation was at its worst in the northern hemisphere, almost the entire surface of the European continent, from Scandinavia and Lapland, to England, Belgium, and central Germany, lay buried beneath one unbroken sheet of permanent ice. But when the conditions were a little less severe, local glaciers radiated from the chief mountain bosses of Scotland, Wales, and the Isle of Man, and ground these deep grooves and scratches on the worn surface of the denuded rock. At length the climate began to mend slightly; and then the plants and animals of the Arctic zone spread uninterruptedly over the whole of northern Europe, from the limit of pack-ice to at least the southern slope of the Alps on the Italian side. Remains of these glacial animals — Arctic lemmings, musk sheep, white hares, reindeers, Alpine marmots, and snowy owls — are still found among the bone-caves and river drift of the interglacial ages in various parts of Europe, from Scandinavia to the Tuscan grottoes. At the same time we may be pretty sure that high Arctic or Alpine plants, adapted to a chilly climate, like the saxifrages, the sibbaldia, the crowberry, and the Swiss veronica, spread over all the plains and valleys of Great Britain and the neighbouring continent.
In those days, we saw good reason to believe when we were examining the stranded southern flora of Cornwall and Devonshire, England and Ireland were united to one another as well as to France and Holland by a broad belt of lowland occupying what is now the bed of the two channels and the German Ocean, so that the mammoth and the cave-bear could roam uninterruptedly from the Yorkshire hills to the rock-shelters of the Dordogne, and from the bogs of Connaught to the then ice-clad summits of the Hartz and the Jura. The dark hunters of the period, who framed the rough, chipped stone hatchets of the Abbeville drift and the beautiful flint arrowheads of the southern French caves, could in like manner range without let or hindrance from Kent’s Hole at Torquay to the Schwatka cavern in Moravia, and from the honeycombed cliffs of Yorkshire valleys to the limestone grottoes among the Alpine slopes. That distribution of land and water easily accounts for the dispersion of Arctic and snow-line plants or animals over all the snowy regions of northern Europe.
But as the cold began to subside, and as a warmer fauna and flora invaded the now milder plains and valleys of central Europe, the glacial types, being less adapted to the new conditions, began to retreat northward towards the Arctic Circle, or upward towards the chilly summits of the principal mountains. Slowly, age after age, the southern plants and animals overran all the lower portions of the continent, cutting the glacial fauna and flora in two, and established themselves as far as the outlying peninsula of Britain, which still continued to form an integral part of the European mainland. After most of the Germanic types had made good their foothold even in this distant region, however, and after the still more southern pæonies of the Steep Holme and the rock-cistus of Torquay had established themselves under the lee of the Cornish and Kerry mountains, on the submerged tract which then stretched out far to the west of the Scilly Islands, the land began to sink slowly toward sea-level; and at last an arm of the Atlantic encircled the whole of Ireland, and still later the waters of two long gulfs which now form the English Channel and the North Sea met together by bursting through the narrow barrier of chalk between Dover and Cape Blancnez. Thus Britain finally became an island group; and, being washed on three sides by the warm current of the Gulf Stream, it acquired an unusually high and equable temperature for a district situated so far to the north and rising into so many chains of low mountains. But not all the plants and animals which inhabit the continent had had time to reach England, which has a comparatively poor fauna and flora; while still more failed to get to Ireland before the separation; and so, the Irish flora contains a larger proportion of Spanish and Portuguese types, while the mass of the English flora, especially in the eastern half of the island, is essentially Germanic.
Even after this change to more genial conditions, however, many of the Arctic plants, though now separated by wide stretches of sea or land from their nearest relatives elsewhere, managed to keep up a vigorous existence in the Scotch Highlands, the Welsh hills, and the greater summits of the Lake district. Some of them still cover vast tracts of country in the north; as, for example, the little green sibbaldia, a tufted Arctic trailer, whose herbage forms a chief element of the greensward in many parts of the Highlands; or the pretty eight-petalled dryas, which stars with its sweet white blossoms the limestone rocks of northern England and the Ulster hills. Among the more common of these isolated old glacial flowers in Britain are the Alpine meadow-rue, the northern rock-cress, the Arctic whitlow-grass, the Alpine pearlwort, the Scottish asphodel, the mossy cyphel, the mountain lady’s mantle, the purple saxifrage, and the red bearberry. Altogether, we have still more than two hundred such Alpine or Arctic plants, stranded among our uplands or in the extreme north of Scotland, and probably separated for many thousand years from the main body of their kind in the Arctic Circle or the snowy mountains of central Europe.
Our pretty little Lloydia here is far rarer in Britain than these low mountain kinds; for it has died out utterly even in Scotland itself, and now survives nowhere with us except on these solitary Welsh summits. Such cases are frequent enough in Britain; for while the moderate mountainous or Arctic species still go on thriving among the straths and corries, the coldest kinds of all have often been pushed upward and ever upward by the advancing tide of southern flowers till they are left at last only on a few isolated mountain tops, where many of them are even now in course of slowly disappearing before the steady advance of the southern types. For example, there is a certain pretty kind of heath, confined to northern or Arctic hill-sides, which till lately lingered on in Britain only on the one mountain known as the Sow of Athole in Perthshire; but of late years it has grown rarer and rarer with each succeeding summer, until it is now probably quite extinct. It is the natural tendency of all such small isolated colonies, whether of plants or animals, to die slowly out; for they cannot cross freely with any of their own kind outside the narrow limits of their own restricted community; and by constantly breeding in and in with one another they at last acquire such weak and feeble constitutions that they finally dwindle away imperceptibly for want of a healthy infusion of fresh external blood.
Fig. 42. — Lady’s Slipper (Cypripedium calceolius).
If I mention a few other like cases (as well as I can remember them on the spur of the moment, for I cannot pretend to give a complete ex-cathedrâ list here on the slopes of Mynydd Mawr) it will help to elucidate the origin and nature of this little colony of mountain tulips. There is a lovely orchid, the lady’s slipper, common in Siberia and Russia, almost up to the Arctic Circle, but now found with us only in one Yorkshire station, where, like the Perthshire heath, it is rapidly verging to complete local extinction. Again, among one family alone, the tufted saxifrage has now been driven to the summits of Ben Avers and Ben Nevis; the drooping saxifrage is extinct everywhere in Britain save on the cloudy top of Ben Lawers; the brook saxifrage lingers on upon the same mountain, as well as on Ben Nevis and Lochnagar; and the Alpine saxifrage, though more frequent in little solitary groups in Scotland and the Lake district, has died out of all Ireland save only on the bald head of Ben Bulben in Sligo. The Alpine sow-thistle, an Arctic and snowy weed, is now dying out with us on the tops of Lochnagar and the Clova mountains. The black bearberry yet haunts Ben Nevis and a few other Highland peaks. The Alpine butterwort has been driven even from the mountains in Scotland generally, but still drags on a secluded existence in a few very northern bogs of Caithness and Sutherland; in this respect it resembles the northern holy-grass, an Arctic plant, which Robert Dick, the self-taught botanist of Thurso, discovered among the high pastures near his native town. This same grass strangely reappears in New Zealand, whither it has doubtless been carried from Siberia by its seeds accidentally clinging to the feet of some belated bird; but then such a solitary case in itself shows how impossible is the explanation of the numerous Scotch and Welsh Arctic plants as due to mere chance; for while in north European mountains similar instances can be counted by hundreds, in New Zealand the coincidence is very rare and almost unparalleled.
The snowy gentian, to continue our list, turns up in a good many little Scotch colonies; but the Alpine lychnis, its companion on the mountain pastures of the Bernese Oberland, is only now known in Britain on the summit of Little Kilrannoch, a Forfarshire mountain, and among the crags of Hobcartin Fell in Cumberland. The bog sandwort, everywhere a rare and dying species, has wholly disappeared from these islands except on the sides of the Widdybank Fell in Durham. Its ally the fringed sandwort loiters late on the limestone cliffs of Ben Bulben in Sligo, as well as on one solitary serpentine hill in the island of Unst among the chilly Shetlands. A tiny pea-flower, the Alpine astragalus, has been driven almost everywhere to the snow-line, but still survives in Scotland among the Clova and Braemar mountains. It is on a single spot in the same exposed Clova range, too, that the closely related yellow oxytrope still grows in diminishing numbers; while its ally the Ural oxytrope holds its own manfully over all the dry hills of the Highlands. I could add to these instances many more; but lunch is waiting to be eaten in the knapsack, and I am loth to tire the patience of my hearers with too long a list of barren names and bare wind-swept mountain summits.
Still, I love to think that the little colony of timid shrinking Lloydias stranded here on the granite slopes of Mynydd Mawr can push back its pedigree in such an unbroken line to so dim and distant a prehistoric past. Ever since the glaciers last cleared away from this boss of smooth stone on whose broad back we are sitting, a tiny group of our pretty mountain tulips has continuously occupied age after age this self-same spot. Originally, no doubt, they covered the whole sides of the mountains and stretched down far into the plains and valleys; but gradually, as the world’s weather grew warmer, they were restricted, first, to the mountain tracts of Wales and Scotland, then to a small Snowdonian district, and finally, even within that shrunken realm, to two or three isolated peaks. Occasionally, I suppose, a seed from one of the three existing Welsh colonies may be carried by accident into the territory of the others; but it is in the highest degree improbable that the stock has ever been reinforced for the last fifty thousand years from any purely external body of its congeners in the higher Alps or in the Arctic regions. The dark small men of the neolithic age, the Aryan Celts of the bronze period, the conquering Roman from the south, the Englishman, the Scandinavian, the Norman, all have since come, and most of them have gone again; but the Lloydias still hold precarious possession of their solitary remaining strongholds. An analogy from the animal world will help to bring out the full strangeness of this extraordinary isolation. Mount Washington in New Hampshire is the highest peak among the beautiful tumbled range of the White Mountains. On and near its summit a small community of butterflies belonging to an old Glacial and Arctic species still lingers over a very small area, where it has held its own for the eighty thousand years that have elapsed since the termination of the great ice age. The actual summit of the mountain rises to a height of 6,293 feet; and the butterflies do not range lower than the five thousand feet line — as though they were confined on Snowdon to a district between the Ordnance cairn and the level of the little slumbering tarn of Glasllyn. Again, from Mount Washington to Long’s Peak in Colorado, the distance amounts to 1,800 miles; while from the White Mountains to Hopedale in Labrador, where the same butterflies first reappear, makes a bee-line of fully a thousand miles. In the intervening districts there are no insects of the same species. Hence we must conclude that the few butterflies left behind by the retreating main-guard of their race on that one New Hampshire peak have gone on for thousands and thousands of years, producing eggs and growing from caterpillars into full-fledged insects, without once effecting a cross with the remainder of their congeners among the snows of the Rocky Mountains or in the chilly plains of sub-Arctic America. So far as they themselves know, they are the only representatives of their kind now remaining on the whole earth, left behind like the ark on Ararat amid the helpless ruins of an antediluvian world. Well, what these Mount Washington butterflies are among insects, that are our pretty wild tulips here among English flowers. They remain to us as isolated relics of an order that has long passed away; and they help us to rebuild with fuller certainty the strange half-undeciphered history of the years that were dead and gone long before written books had yet begun to be.