ivy-leaved toadflax


Значение термина ivy-leaved toadflax в knolik


ivy-leaved toadflax - Ivy-leaved Toadflax (Linaria cymbalaria)
ivy-leaved toadflax - The awkward, ugly, English name ill befits a little plant of such delicacy and charm. Scarcely better, either, is "Mother of Thousands," the name by which our country folk often know it, and which has special reference to the apparently unending succession of bright little flowers that it produces from spring to autumn. Far more sympathetic and appreciative is the name given to it by its own countrymen of Italy, who term it the "Herb of the Madonna," and dedicate it to her because of its grace and beauty. As is the case with so many of the very attractive plants that to-day we gather wild, we cannot actually claim it as a Britisher, for it came to us from the southern countries of Europe in comparatively recent times. In the sixteenth century it was counted as purely a plant for cultivation, but being very hardy and adaptable it has since completely naturalised itself, and is no longer to be classed among the aliens.

Clinging to the mortar of some old wall, and nourishing happily where the conditions of life seem most precarious and ascetic, its slender, trailing stems droop gracefully over the stones, here and there sending out little rootlets from the nodes so that no opportunity may be lost of strengthening its hold. The delicate, smooth stems carry delicate, picturesque and also perfectly smooth leaves that, with their five-rounded lobes, recall certain of the less angular ivy leaves - hence its common name. Some of the leaves, even when full grown, are very small - the wall does not offer a luxuriant living - but where more soil has collected in the crannies they may be as much as a couple of inches across. Though on the face they are a shining, vivid green, on the back they are pale and dull, and often tinted with purple. To the taste they are slightly acrid, but they possess no medicinal quality, though once they had an unenviable notoriety. In the earlier days of the eighteenth century a Neapolitan woman, named Tophania, concocted and sold a secret poison which came to be known as "Poudre de Succession." Its administration caused the victim to die a lingering death, as though of some slow disease, and it is said that some six hundred people died from its effects before the arch-poisoner was found out. An analysis of "Poudre de Succession" made by the physician to Charles V., King of the Two Sicilies, showed that it consisted of a liquid known as Aqua Cymbalariæ, made from the leaves of the Ivy-leaved Toadflax, in which was dissolved some compound of arsenic. It was, of course, the arsenic, not the little Toadflax, that was at the root of the mischief.

All through the summer the lilac flowers follow one another; as one fades another takes its place. They are held well forward on long stalks, "face on" to the sunshine, and it is at first difficult to realise that the bright, five-petalled flower with the light centre is identical in structure with the great Yellow Toadflax of the hedges, and almost identical with that of the snapdragon. But if the flower be turned about, it will be seen that the petals form the same sort of closed box, while an experimental pinching will make it "yawn" in the selfsame way. The only difference between the snapdragon and the Toadflax is that in the latter the lower part of the corolla runs backwards as a long spur, while in the snapdragon such a possibility is only indicated.

Let us notice closely the structure of this remarkable two-lipped corolla.

The upper lip is small and dark purple in colour; the two lobes that stand erect at the mouth of the (lower speak of the fact, that two out of the five petals combine to form it. These lobes are streaked with a few purple lines, or "honey-guides." The lower lip is much larger. Three petals make it up and their three tips turn downwards as three pale-lilac lobes. A third of the way back it hinges with the upper lip to form a tube, and after passing the point of insertion of the stem forms the aforementioned spur. Above the three lobes two big, pale yellow mounds divided by a groove arise, and are a capital alighting platform for an insect. If we make the flower "yawn," we can see down its throat and note that two rows of orange-coloured hairs run back from the mounds and outline a channel, while there is a small tuft of hairs by the hinge on either side of the cavity. The orange hairs on the floor of the throat cavity keep the insect's head directed upwards, those on either side prevent it straying from the straight path. Up above in the roof are four stamens, their white heads in two pairs, one pair in front of the other.

They are open and showing their white pollen. Between them runs the style from the little ovary at the bottom of the tube. At the base of this minute ovary is a gland which secretes honey, and this trickles along a groove between the stamens into the spur, and is there collected. Both stamens and stigma seem to mature at the same time.

Cross-fertilisation can only be brought about by some insect, chiefly one of the smaller bees, settling on the mounds. The closed mouth of the flower promptly opens under the weight, and the insect inserts its long proboscis into the cavity in search of the honey in the spur. Its head will inevitably strike the pollen-dusty anthers in the roof, and so, when it flies away, it carries pollen on its head as well as honey in its pouch. As it backs out of the cavity the flower snaps to again.

But the most remarkable thing happens as the flower fades. Its stalk, hitherto so bravely holding out the flower, draws back under the leaves, and as the seed capsule forms and ripens it actually curves towards the wall and is only arrested by coming into contact with it. The capsule is thus placed in some nook or crevice. It is a most extraordinary instinct that causes it to act thus - a measure of sheer self-preservation, indeed - for, if the capsule were held out as the flower was, when it burst and released its tiny black seeds they would all fall to the ground and, as the offspring of a parent whose home is a wall, be lost to posterity. As it is, the little seeds lie in the crevice, and since they are ridged and roughened on the surface, they do not easily slip out of it.

This little Toadflax has figured prominently and happily on one or two occasions. It is said that when Linnæus as a young man came to Oxford he, as the disturber of botanical tradition, was received somewhat coldly by the senior botanists there. But as he walked in the college garden with several dons interested in botany, masses of this plant on the garden wall caught their eye. Dillenius, the senior professor, stopped and spoke of various difficulties he had recently found in connection with it. Linnæus, however, was able at once to explain them so clearly away that the professor's coldness and prejudice were broken down, and admiration for the young Swede took their place.

Again, a plant of the Ivy-leaved Toadflax was once used to point a moral to the Chancellor of the Exchequer. In 1850 a deputation approached him with reference to abolishing that most unpopular and iniquitous tax - the Window Tax. To illustrate their contention that the blocking out of light was a direct injury to health and prosperity, they produced an Ivy-leaved Toadflax, part of which had grown with full access to the sunlight and part of which had been accidentally cut off from such access. The well-lighted portion was flourishing, with fine leaves, flowers and seeds, the light-starved portion was weak, small, flowerless and fruitless. The argument was most telling, the Chancellor of the Exchequer rational, and the tax-resisters gained their point.

Рядом со словом ivy-leaved toadflax в knolik


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