. Botany of the living plant. Botany. APPEND IXf A 537 any bracts subtending them. Centrally are the yellow florets of the disc, peripherally the ray-florets. Each disc-floret consists of : Calyx, represented only by a rim round the upper limit uf the inferior ovary. There is no pappus. Corolla, petals 5, gamopetalous, superior. Androeciitm, stamens 5, alternating with the petals, epipctalous, inserted by separate filaments upon the throat of the corolla, but with the anthers united laterally into a tube (syngenesious). Gynoecium, carpels 2, antero-posterior, syncarpous. Ovary inferior, uni- l
. Botany of the living plant. Botany. APPEND IXf A 537 any bracts subtending them. Centrally are the yellow florets of the disc, peripherally the ray-florets. Each disc-floret consists of : Calyx, represented only by a rim round the upper limit uf the inferior ovary. There is no pappus. Corolla, petals 5, gamopetalous, superior. Androeciitm, stamens 5, alternating with the petals, epipctalous, inserted by separate filaments upon the throat of the corolla, but with the anthers united laterally into a tube (syngenesious). Gynoecium, carpels 2, antero-posterior, syncarpous. Ovary inferior, uni- locular, containing a single anatropous ovule. Style elongated, and bearing up through the tube of the anthers the two lobes of the stigma, which diverge beyond it in the later stages of flowering (Fig. 442, vii.) The white ray-floret consists of ; Calyx, as before. Corolla, petals 5, gamopetalous ; tubular below, elongated above into a narrow strap- shaped ray representing the three anterior petals, the two posterior being here obsolete. Androeciitm, absent. Gynoecium, as before (Fig. 442, v.). Fruit. Each flower proS^iices a dry achene, which at maturity is shaken out from the protecting involucre. There is no pappus. Pollination. The mechanism is here essen- tially the same as in Groundsel, but with addition of the attractive ray-florets. In the first flowering stage the disc-florets offer pollen ; in the second stage the expanded stigmas to the insects that are attracted by the colour and honey (iii. iv.) Any crawling insect will effect crossing. But if this fail? self-pollination is also possible (44) A third more elaborate type is seen in Cornflower {Centaurea cyanus, or C. montana will serve). The general structure is the same, but the ovoid head is tightly enclosed by the appressed bracts with brown margins. The receptacle is flat and bristly. The flowers are all tubular, but the outermost are neuter, and coloured, with long tubular two-lipped and 5-lobed corolla, and ab
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