Kitabı oku: «Moorland Idylls», sayfa 10
XXXII.
THE HAREBELL
Few English flowers are better known than the harebell; yet I wonder what proportion of all those who love it well in its summer beauty would be able to account for its botanical name of Round-leaved Campanula. “Round-leaved!” most people would say; “why, its leaves are slender and narrow and grass-like.” And so they are, indeed, in the later state in which you pick in July the graceful pensile blossoms. But the flowering stage of every plant is, after all, but its momentary reproductive period; it represents, so to speak, the golden prime of the full-grown individual. Before that stage is attained, the plant itself has to grow and prepare for flowering; it has to pass through its adolescence and its formative epoch. Now, the harebell is a herb whose two ages of life are singularly different; if you saw it in its green youth, when it is devoting itself wholly to feeding and storage, you would never imagine it was the self-same plant as that whose tall and very slender stem supports in later life the scattered group of drooping blue bell-flowers with which you are familiar.
Here on the dry sandbank, beside the path that runs obliquely across the moor, I see half a dozen harebell-worts in the first, or caterpillar, stage of their existence. The metaphor is less violent by far than you would at first imagine, for in its earlier days the harebell, like the caterpillar, does nothing but eat and lay by for the future; while in its second or flowering stage it does nothing but put forth its tender blue blossoms, which answer to the butterfly both in their attractive beauty and in the fact that they serve to produce the seeds (which are the analogues of eggs) for the coming generation. In the purely preparatory, or hard-eating, stage, the harebell has no stem or branches to speak of; it consists of a rosette of large orb-like leaves, often heart-shaped towards the stalk, and pressed close to the ground in a spreading circle. Each such rosette springs in April from a buried rootstock, which, in loose loamy soil, like that of these Surrey moors, is often intricate; it burrows in and out with strange instinct among the dry sand and stones, in search of such rare moisture as it can manage to find for itself. But though water is scarce, access to light and air is easy; so the large round leaves, lying close on the bare ground, get sunshine in abundance, and feed to their hearts’ content upon their proper food – the carbon in the atmosphere – while vegetation around is still low and backward. In this stage they may be compared to the rosettes of London-pride, which are similarly clustered, but which do not die down as the flower-stem advances.
About June, however, the harebell plant has eaten and drunk enough to venture upon leaving its caterpillar stage behind, and sending up the loose cluster of waving blue flowers which represent its butterfly. In order to do this, and overtop the tall grasses which have sprouted meanwhile, it withdraws the whole of the living green-stuff from its heart-shaped root-leaves, and uses up the active material they contain in building its flower-stem. Thus, as the stem lengthens, and the buds begin to swell, the lower leaves die away altogether; only a few quite dissimilar and very narrow blades on the ascending branches now represent the original foliage. After the flowers have set, even these last disappear, or dry up on the stem, their living material being withdrawn in turn to supply food for the developing seeds. This may seem odd at first, but it is a common incident in many life-histories of plants and animals. As a rule, indeed, the butterfly or winged stage of most insect lives is wholly devoted to a marriage flight; and there are several winged insects which never feed at all in the perfect state; they use themselves up in the formation of eggs, and then die of inanition.
Most of the sister campanulas, like Canterbury bells, are stiff and coarse and hairy plants, without grace or elegance; but that is because they haunt woods and copses, or overgrown hedgerows, where they are sheltered from the wind, and enabled to grow large and rampant. The harebell, on the contrary – the oread of its race – is a denizen of the open, wind-swept uplands; it loves the moors and heaths, the bare hilly pastures; and it has learnt in consequence to bend lightly before the breeze, springing up again as those invisible feet pass on, which gives it its familiar slenderness and elegance. The hanging domes of the flowers are entered from below by bumble-bees, which are strong enough to push aside the fringed and close-set teeth that edge the base of the stamens, put there on purpose to baffle less useful honey-thieving visitors. Equally strange is the egg-shaped capsule which, later on, contains the seeds; it opens by five short clefts near the top. The actual reason for this arrangement is itself a somewhat odd one. The seeds can only drop out through the pores or clefts when a high wind blows and sways the waving stem violently. At such times the little grains get carried by the breeze to considerable distances; and this serves not only to disseminate the kind, but also to carry the majority of the seeds to unoccupied spots, where rotation of crops can thus be secured by letting the young plants sprout at a distance from the soil exhausted by their mother. Similar devices for securing rotation are common in nature; they often occur in species like this, whose seeds seem at first sight wholly unprovided with wings, or floats, or other means of locomotion.
XXXIII.
THE UNTAMABLE SHREW
By the hedgerow in the garden my terrier, Freckle, has just come across two pugnacious shrews, engaged in one of their sanguinary battles. The high belligerent parties are not exactly formidable to outsiders, it is true, being not quite three inches long apiece from snout to haunches, not counting an inch and a half of tail, oddly square in outline, to finish off their appearance. Yet they are savage fighters, for all that, in their intertribal quarrels. When shrew meets shrew, then comes the tug of war. It very seldom happens that they do not join battle, and the victor in the fray usually kills and eats his discomfited rival. So fierce a heart in so small a body is rare, but the shrew knows not what fear means. This particular pair of combatants were so automatically intent on the fortunes of war that Freckle was upon them and investigating their nature with her inquisitive nose before they even woke up to the fact of her presence.
Most people seem to confuse shrews with mice; but, indeed, our small combatants are widely different creatures from those timid little beasts; they belong to a wholly different group of mammals. Mice are rodents, descendants of the same common ancestor with the rats and dormice, and not remotely related to the squirrels and the rabbits. Shrews, on the other hand, are insectivores, first cousins of the moles, the hedgehogs, and the desmans. Externally, it is true, they resemble considerably the mice and voles; but those who have followed the course of recent natural history must be aware by this time that “appearances are deceitful.” If an animal looks very much like something else, the chances are that it is altogether different. This is particularly the case with the insectivores and the marsupials, each of which great groups has independently developed a series of forms absurdly like the mice, the squirrels, the porcupines, and the jerboas, because each fills approximately the same place in nature. For example, small mammals which creep about among grass and matted herbage are likely to assume a mouse-like shape. This has happened among rodents in the case of the mice and field-voles, among insectivores in the case of the shrews, and among Australian marsupials in the case of the pouched kangaroo-mice. Our English shrew is a pretty little creature of this common type, with thick soft fur like a mouse’s, only a trifle redder, and so mousey in shape that it is seldom discriminated from the true mice, save by naturalists and gamekeepers. Even externally, however, it differs much from mice in its long pointed snout – a marked insectivorous feature – as well as in its square and abruptly cut-off tail, where the mouse’s is rounded, tapering, and slender. When you come to the teeth and internal anatomy, however, the creature is an insectivore, displaying at once quite a separate character.
Mice, as everybody knows, feed mainly on seeds and grains, though they are fairly omnivorous, and do not despise either bees or beetles. But the shrew, less promiscuous, eschews all vegetable foods; he makes his diet entirely of insects, worms, and slugs, of which he devours an incredible number. Hence he haunts for the most part dry fields and gardens, where such prey is abundant. His preference is also for a soft sandy or light loamy soil, in which he can burrow with ease with the muzzle alone, for his slender feet are ill adapted for digging through hard earth or clay. A relative of the mole, he makes long runs, like his cousin, through the soft surface-soil in search of insects; but, unlike the mole again, he has preserved his small, keen eyes intact, and lives, on the whole, as much above ground as beneath it. Yet his cousinship stands him in small stead with his big purblind relation; for moles catch and eat shrews in considerable numbers. This is not to be wondered at, perhaps, when one reflects that the unnatural shrews also eat one another. Cannibalism, indeed, is an unamiable trait common to man and the insectivores. Weasels, owls, and cats are also great shrew-killers; though, strange to say, the shrew, when killed, is by no means always eaten. I put this down in the main to the powerful scent-glands, which run along the side of the body, or occur at the root of the tail, in most species of shrew, and which secrete a very strong and odorous liquid. This liquid, I fancy, is partly protective, partly attractive to the opposite sex. It would seem to be distasteful to outsiders, but not unpleasant to insectivores themselves, for cats will kill a shrew from pure love of sport, or by mistake for a mouse, but will seldom or never eat it, whereas shrews themselves and moles have no such prejudice. Owls, also, eat shrews, in spite of their flavour. I believe such sexually attractive scents almost always coexist with the pugnacious temperament. All musky-perfumed animals fight savagely with one another for possession of their females, as do also those with marked frills or top-knots.
Shrews, though comparatively seldom seen by incurious eyes, abound by myriads in most parts of England. Every summer they increase sevenfold; but as autumn approaches, and food grows scarce, they die off in their thousands from cold and hunger, as I gather. So many of them then strew the footpaths in sandy districts that country people have a quaint superstition about them; they say a shrew cannot cross a church-path without dying instantly. What constitutes a church-path is somebody having once gone to church along it. The truth is, dead shrews abound equally in the grass and thickets; but, of course, only those are seen which happen to die in the open. This is but one out of many hundred odd superstitions about the shrew, which may be regarded, indeed, as the most wizard-like animal now left in England.
