. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. CARYOPHYLLEAE 183 sunshine, forming an almost plate-like disk, measuring about 8 mm. in diameter. The five white spathulate petals are about the same length as the bright green sepals. Of the ten stamens, the five opposite the sepals mature first. They are then nearly erect, and project from the fiovifer about i mm. The five other stamens—which have meanwhile rested on the petals—next mature, elongating till they are as long as the outer ones. It is only at
. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. CARYOPHYLLEAE 183 sunshine, forming an almost plate-like disk, measuring about 8 mm. in diameter. The five white spathulate petals are about the same length as the bright green sepals. Of the ten stamens, the five opposite the sepals mature first. They are then nearly erect, and project from the fiovifer about i mm. The five other stamens—which have meanwhile rested on the petals—next mature, elongating till they are as long as the outer ones. It is only at this stage that the stigmas unfold. At the base of the ovary there is a large yellow nectary between each pair of stamens, which secretes so abundantly that the intervals between the pairs of stamens are completely filled with nectar. In spite of its abundant nectar the flower is seldom visited by insects. I saw no visitors in the island of Rom, though I watched for a long time during fine weather. From dehisced anthers, however, pollen frequently falls into the flower, and this may be carried by the wind to the stigmas of the same plant, or of neighbouring ones. Small grains of sand are constantly to be found in the flowers, into which they have been drifted by the wind, and as these may be blown along from blossom to blossom they possibly serve as occasional agents of pollination. During dull weather the flowers close, so that automatic fig. 53. Honckenya pepioidcs, EUrh. self-polUnation is then possible. !:;:nlffi?s™:;tafe',r; In Greenland, Iceland, north Norway, Spitz- from above, k, sepal; p, petal; «, stamen of _ ,. J- i. Tir • '^^ outer whorl with dehisced anther: o', bergen, and Nova Zemha—accordmg to Warmmg stamen of the inner whorl, with anther stiii —hermaphrodite flowers are very rare, and closed; s, immature stigma; ?, sand-grain. dioecism, polyoecism, or monoecism almost always obtains. Warming observed fruits to be set in Greenland. This spec
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