Thus, an insect bearing pollen from one flower will, in entering a second, deposit the pollen on the stigma in backing out of a flower, the pollen which it bears will not be rubbed off on the stigma of the same flower. The shelf-like transverse projection on the inner whorled underside of the stamens is beneath the overarching style arm below the stigma, so that the insect comes in contact with its pollen-covered surface only after passing the stigma in backing out of the flower it will come in contact only with the non-receptive lower face of the stigma. ![]() The shape of the flower and the position of the pollen-receiving and stigmatic surfaces on the outer petals form a landing-stage for a flying insect, which in probing for nectar, will first come into contact with the perianth, then with the three stigmatic stamens in one whorled surface which is borne on an ovary formed of three carpels. The iris flower is of interest as an example of the relation between flowering plants and pollinating insects. The three styles divide towards the apex into petaloid branches this is significant in pollination. ![]() They are united at their base into a floral tube that lies above the ovary (known as an epigynous or inferior ovary). Some smaller iris species have all six lobes pointing straight outwards, but generally limb and standards differ markedly in appearance. The three, sometimes reduced, petals stand upright, partly behind the sepal bases. In the centre of the blade, some of the rhizomatous irises have a "beard", a row of fuzzy hairs at the base of each falls petal which gives pollinators a landing place and guides them to the nectar. They expand from their narrow base (the "claw" or "haft" ), into a broader expanded portion ("limb" or "blade" ) and can be adorned with veining, lines or dots. The three sepals, which are usually spreading or droop downwards, are referred to as "falls". The inflorescences are in the shape of a fan and contain one or more symmetrical six-lobed flowers. The bulbous species also have 2–10 narrow leaves growing from the bulb. The rhizomatous species usually have 3–10 basal sword-shaped leaves growing in dense clumps. They have long, erect flowering stems which may be simple or branched, solid or hollow, and flattened or have a circular cross-section. Irises are perennial plants, growing from creeping rhizomes (rhizomatous irises) or, in drier climates, from bulbs (bulbous irises). Description Rhizomes of ornamental irises Illustration of an iris flower with highlighted parts of the flower Three Iris varieties are used in the Iris flower data set outlined by Ronald Fisher in his 1936 paper The use of multiple measurements in taxonomic problems as an example of linear discriminant analysis. dichotoma) are currently included in Iris. tuberosa), and Pardanthopsis (vesper iris, I. ![]() domestica), Hermodactylus (snake's head iris, I. The often-segregated, monotypic genera Belamcanda (blackberry lily, I. A common name for some species is flags, while the plants of the subgenus Scorpiris are widely known as junos, particularly in horticulture. ![]() As well as being the scientific name, iris is also widely used as a common name for all Iris species, as well as some belonging to other closely related genera. Iris is a flowering plant genus of 310 accepted species with showy flowers.
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