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yellow rattle


Значение термина yellow rattle в knolik


yellow rattle - Yellow Rattle (Rhinanthus crista-galli)
yellow rattle - An extraordinary looking plant of sinister countenance, an individual that at once raises a feeling of suspicion in the mind t Ruddy, thin, square stems up to a foot in height, leaves that are stalkless triangles set opposite to one another in pairs upon the stem and cut into great jagged teeth, and spikes of bright yellow, hooded flowers of peculiar outline make it up. The substance of the leaves is harsh and their surface is covered with minute, rigid hairs all pointing tipwards, so that it is impossible to pass the leaf from apex to base across one's lips without great unpleasantness, though it will run smoothly enough along the lip over the hairs if the direction be reversed. This characteristic is to prevent small, wingless insects intent on rifling honey or pollen, from creeping along the leaves to the stem and so up to the flowers. The bracts or leaves at the base of the flowers are still more jagged than the leaves, and it is to them that it owes its specific name, Crista-galli, or "cock's comb," a name that it carries in other countries besides ours. Perhaps, too, the shape of the flower, with its fanciful suggestion of the head of a fowl, has emphasised its association with the idea of a cock, and then by easy transference of thought to St. Peter, and since it is in the zenith of its flowering about St. Peter's Day - June 29th - it was in olden days taken as the flower of that festival. "The yellow floure, called the Yellow Cockscombe, which floureth now in the fields is a sign of St. Peter's Day whereon it is always in fine floure in order to admonish us of the denial of our Lord by St. Peter," said an old writer.

The most remarkable feature of the flower is, perhaps, the great inflated calyx, like a flattened bladder, ending in four small teeth. This inflation no doubt prevents thieving bees from getting at the honey by boring, but its main service to the plant comes later when the seeds have to be dispersed. Out of the bladder and beyond the four teeth rises the great hooded corolla, with a very thick tube as a neck, which is hidden within the calyx. Under the hood in front are a couple of purple teeth - just a dark edge - to point out the opening. Below the teeth is a platform of three frilly lobes. Thus the corolla is of the two-lipped variety so usual in the Scrophulariaceæ family to which the plant belongs. Inside, and right under the hood, are two pairs of stamens, with white waved filaments and black heads, and each pair have their heads joined by white matted hairs, so that they form a flat arch across the flower, and incidentally a very effective sprinkling apparatus. The anthers open on their inner faces, hence their white spheroidal pollen falls among the matted hairs and lies there ready for the critical moment. In the centre of the flower is a flat, almost circular ovary bulging a little with seeds within. A long column from it curves round closely under the hood, and just puts its tip out of the opening above the purple teeth. In front of the ovary is a projection of the fleshy base, and it is here that honey forms.

Now, though the Yellow Rattle has many visitors, bees are those that it specially desires and for which it caters. Müller, carefully watching, saw no fewer than nine different sorts of bee visit it. And this is the order of the day when a bee pays a call: it hovers before the flower and makes straight for the purple-outlined opening under the hood, alighting on the firm, frilly platform of the lower lip, which is well able to bear the weight. Its head immediately touches the delicate projecting tip of the ovary column just above. Any pollen on its head is thus transferred. But to get to the honey manufactured in the lobe of the ovary and stored in the corolla tube it must dive under the two narrow arches of the anther pairs, and between the curving, stiff, filament columns that support them. These are rudely shaken, and out falls the pollen from the matted hairs like water from a shower-bath, sprinkling the insect in a line on the top of its head, exactly where the stigma had just rubbed and precisely where the stigma in the next flower will rub later. The bee is bound to keep in a straight line when entering the flower, because the stamen filaments are beset with sharp spines that prevent it straying. Also the sprinkling cannot be promiscuous, since a fringe of hairs on the lower edge of the anthers on either side keeps the pollen shower confined between them. Later the style curls downwards and inwards to its own stamen for self-fertilisation if necessary.

When the flower is fertilised the corolla drops off, leaving behind the inflated and still-growing calyx, looking now like a closed purse - there may be a dozen of them arranged down the stem. In Jutland the peasants call the plant "Löki's Purse." Since Löki is the personification of malice and subtlety, we have again the suggestion of something sinister arising, a suggestion justified, as we shall see. The "purses" now rapidly lose their greenness and become dry and scaly and rustle and rattle in the wind. Hence the names "Yellow Rattle" and "Rattle-boxes" for the plant. "When the Yellow Rattle rattles then the hay is ripe," say the Swedes. By August all that is left of the vivid yellow and green herb of St. Peter is a pale, death-like spike, which looks like a ghost and recalls a chattering skeleton. "Penny Grass" and "Hen-penny," calling to mind the days of silver pence, are old country names derived from the aspect of the plant at this stage.

But it is not very easy for seeds - even though they each possess a circular wing of their own - to get out of a purse like this, which opens only at the top, especially as they are also in an inner, though also open, purse - the ovary - so here the bladdery calyx comes to the rescue. It catches the wind with considerable force, and rocks to and fro vehemently whenever there is a breeze. Out jerk occasional seeds which are caught by the same gust, and so, aided by their own wings, they are carried away and scattered, though not to any great distance. Indeed, the young plants are generally found growing close round their parent, and regular colonies of considerable size are formed - "It might have been sown by the bushel," remarks Kerner.

But if one watches the growth of one of these seedlings, one becomes aware that the Yellow Rattle has a secret sin, one that, though hidden, cannot be completely concealed. It has strong leanings towards parasitism. At first the little plant, aided by a good stock of reserve material provided by the parent, makes a brave start on a life of independence, but soon it puts out from its roots below ground rounded suckers of some size with thickened margins, and these lay themselves on the roots of the grass or of other plants that may be near, and gripping the root round, perhaps half its circumference, draw from it by means of many absorption cells the rich sap that it has provided for its own use.

The Yellow Rattle, to be quite fair to it, does not depend wholly upon the other plant; it is not a complete parasite, or it would not have such fine gay leaves and flowers; it does part of its own work in building foodstuffs from the salts and water of the soil and the gases in the air, but it supplements its income in this illegitimate way. For a long time the true nature of the plant was quite unsuspected, though it had always been eyed with disfavour and considered to injure the meadows; where it grew in any abundance farmers said it "burned" their grass, and an Elizabethan writer remarks: "It grows in dry medowes and pastures, and is to them a great anoyance." But in 1847 a French botanist, a M. Decaisne, hazarded the suggestion that the plant, albeit green, was a parasite, a somewhat startling proposition to British botanists, since at that time our parasites were supposed to be always brown and leafless - the mistletoe excepted. But experiments proved the suggestion correct; the Yellow Rattle could not flourish if it were grown away from the neighbourhood of other plants, being stunted, almost flower-less, and quite seedless in those circumstances. Nowadays we are fully aware that the family Scrophulariaceæ, as represented in Great Britain, has within its borders five groups of plants that are semi-parasites, namely (1) the three bartsias, (2) the eye-bright, (3) the Yellow Rattle, (4) the red rattle, and the meadow lousewort, (5) the four cow-wheats; and all of these attempt to get a living more easily by niching from their neighbours.

Рядом со словом yellow rattle в knolik


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