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yellow corydalis

Значение термина yellow corydalis в knolik

yellow corydalis - Yellow corydalis (Corydalis lutea)
yellow corydalis - Great tufts of filmy leaves - curiously reminiscent of maidenhair and interspersed with clusters of pale yellow bird-like flowers - were decking the old red wall behind the herbaceous border. Long ago, no doubt, the Corydalis had been an invited guest into that garden, welcomed for the delicate charm of its colour and form, but, like other guests have been known to do, it had a little overstepped the limits of its welcome and a ruthless hand was tearing it out by the armful. It offered little opposition, for though it had "many crambling threddy roots," as an old writer said, and they were moreover, "somewhat thicke, grosse and fat," yet the crumbling mortar of the old wall gave it no encouragement to resist. It seemed hard on the plant, whose charms became even more insistent as one saw it more closely. Let us sum them up shortly.

The pale, wax-like stems are tinted with pink, and carry a curious suggestion of translucence about them, especially where they swell at the junction of leaf-stalk and main stem. The leaves are very many and closely intermingled in such a way that one keen observer described them as "confusedly placed" upon the stems. Part of this apparent confusion is due to their being very finely cut into many segments. Each is first divided into three main divisions, then each division is cut up into still finer divisions. On the top surface the colour is a subdued and delicate green, below it is still us paler, and more delicate and subdued, so that when the wind rustles the leaves the green colouring of the foliage has a "shot" effect, as one says of a silk woven with strands of two colours.

Eight or nine, possibly even a dozen, flowers, cluster together at the end of a stalk, but since the flowers all tend to turn in one direction - the direction of greatest light and that from which they may anticipate the advent of their visitors - the clusters have a one-sided appearance. They are particularly interesting, both for the elaborate plan on which they are designed and for the failure which so often attends their complex schemes. Each flower is set, as it were, across the end of its stalk - that is to say, the stalk appears to come from the side of the flower rather than from its end. It has only two little sepals, and the effect of these is entirely lost, since they are very minute and are coloured, moreover, very like the petals. The four petals form a closed box of peculiar shape. The top petal is much the largest; in front it turns upwards and forms a kind of portico; at the opposite end it curls over beyond the stalk in a thick, hollow spur. The two lateral petals are alike and smaller, and form the sides of the box. Towards the front each carries a little flap on its outer side. The lowest petal, which forms the floor of the box, is very interesting - the diagram shows its construction. Along its length runs a trench, open near the petal's base, then closing-over, and widening out at the tip into a definitely marked depression - it is rather suggestive, in fact, of a pipe running into a pool.

The six stamens are collected into two groups, each group having a single broad filament with three minute branches at top, each branch carrying an anther. The pollen grains contained in the anthers are remarkable in that many different crystalline forms are found side by side in the same anther. Honey collects in the round, thick spur of the top petal, being exuded from a projection of the tipper filament into the spur. The lowest petal might well be constructed for conducting the honey into the pool at its tip with a view to offering a "taster" to visitors, but there is no proof that this happens. The dark green seed-case is hidden in the petal box, and a long, transparent-looking filament carries the yellow stigma. Stamen-groups and ovary, style and stigma are completely enclosed in the box formed by the four petals. Kerner calls attention to the point "that Corydalis is almost unique amongst flowers in that it is lopsided, i.e. the spurred petal is not in the median plane of the flower (as in the generality of zygomorphic flowers), but is inserted laterally."

Now, apparently what the plant designs should happen is this: a big humble-bee approaches the flower "face on" and straddles across the side petals under the portico. The two flaps, already mentioned as on the smaller side petals, serve like stirrups to steady it and give it the purchase necessary for it to thrust its head with determination into the box, which is opening under its weight.

As it inserts its proboscis into the spur a curious lever mechanism, forcing out stamens and stigma, scatters the pollen from the stamens upon its abdomen. It then withdraws its head and flies away. But the truth is that, after all this elaboration of plan, insects seem to care little about the Corydalis, and the plant's visiting list is a very short one. Indeed, it does not treat its visitors well; it is rather like the case in Æsop's Fables of the stork inviting the fox to a meal. The petal box of the flower is very long, the honey in the spur only reaches up a little way; therefore, when a hive bee settles upon the flower and goes to the trouble of pressing it open and attempting to partake of the honey provided, it finds its proboscis is too short to reach the desired nectar. Therefore, it must needs depart unsatisfied, its labour wasted. A humble-bee, whose proboscis is longer, fares a little better; it can, perhaps, just touch the honey, but it cannot sip it with ease; therefore it, too, goes away dissatisfied, and in neither case is there any encouragement to continue visiting other flowers of the Corydalis kind. This is particularly bad policy on the part of the plant, because it has so arranged its affairs that no flower can be fertilised by the pollen from its own stamens; the ovules are absolutely irresponsive if the pollen grains that fall upon the stigma are from the anthers adjacent to it; even if the pollen comes from other flowers on the same plant there seems little result; it has, therefore, made itself absolutely dependent upon the kind offices of bees to convey the pollen from one plant to another. But the bees, wholly deluded if of the smaller hive kind, unsatisfied if of the larger "humble" sort, are not going to be altogether deprived of their anticipated feast, and so we find them turning burglars and biting through the tube from outside, and thrusting their probosces through the opening directly into the honey pool. Dishonesty pays in their case, they sup their fill; the flower is punished for its maladroit arrangement, it loses its honey and no service is performed in return. It is, therefore, not surprising that it often fails to set seed. When it does succeed, it bears small, narrow pods containing several seeds, which pods open by two valves.

There are two Corydals which are now found growing wild in Great Britain: firstly, the Yellow Corydalis of our picture and description, known sometimes as the "Yellow Fumitory," and also "Mother of Thousands," from the very many little yellow flowers it bears; secondly, the Climbing Corydal, which has small white flowers and climbs by means of its leaf-stalks, which possess delicate tendrils. But neither species is a true native of this country; the Yellow Corydal comes from Barbary and southern Europe, the Climbing Corydal is native rather of western Europe. Both species blossom in June and July, and prefer stony places, the Yellow Corydal in particular is very much at home on old garden walls. Its family is that of the Fumariaceæ, and its nearest British relative the Fumitory.

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