. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. 6o6 ANGIOSPERMAE—DICOTYLEDONES ' Pyreneenbl.,' p. 363.)—This species is monoecious. Twenty to thirty male disk- florets with a considerably larger number of female ray-florets are aggregated into a head 4 mm. in diameter. Conspicuousness is enhanced by the cauline leaves, which are covered with a thick white hairy coat and surround the corymb of tiny heads to form a whitish star of 20 to 40 or 50 mm. in diameter. The ray-florets possess a narrow corolla-tube
. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. 6o6 ANGIOSPERMAE—DICOTYLEDONES ' Pyreneenbl.,' p. 363.)—This species is monoecious. Twenty to thirty male disk- florets with a considerably larger number of female ray-florets are aggregated into a head 4 mm. in diameter. Conspicuousness is enhanced by the cauline leaves, which are covered with a thick white hairy coat and surround the corymb of tiny heads to form a whitish star of 20 to 40 or 50 mm. in diameter. The ray-florets possess a narrow corolla-tube 2^-3 mm. in length, and secreting no nectar. The style, of which the branches are closely beset with stigmatic papillae internally, projects i mm. from it. The style is covered externally with short sweeping-hairs for some distance below the point where it divides. In male flowers the style does not bifurcate, and therefore possesses no trace of stigmatic papillae. It is in the form of a cylindrical rod covered with papillose sweeping-hairs at its end, and serving to brush out the pollen from the anther-cylinder. These pseudo-hermaphrodite male florets possess a. Fig. 198. Gnaphaliunt Leontopodium, L. (after Herm. Muller). A. Group of seven heads (nat. size). B. Female ray-floret without the pappus (x 7). C. Male disk-floret, do. (x 7). D. End of the style of a male floret, which acts as a brush ( X 80). E. Do. of a female floret (x 80). /j sweeping- hairs ; gr^ style ; ffi', ovary ; po^ pollen-grains; st^ stigmatic papillae. corolla-tube about 2 mm. in length, expanding into a bell scarcely i mm. long, from which the anthers and style project. Nectar is secreted at the base of the style. Schroter describes nectar-florets, which resemble the male ones. They possess a vestigial rudimentary style with quite short sweeping-hairs, but no stamens (Ber. Schweiz. Bot. Ges., v, 1895, p. 5). Kemer states that the stigmas of the female florets become receptive several days before th
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