. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. 222 ANGIOSPERMAE—DICOTYLEDONES sometimes so short that the stigma touched the anthers, and automatic self-pollina- tion consequently took place. Nyhuus found this latter form exclusively at greater elevations near Troms0 on the Dalfjeld, but the long-styled one predominated at stations of lowel level. Kerner says that the flower is at first adapted for crossing, but later on, when the secretion of nectar has ceased, pollination by wind becomes possible. When
. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. 222 ANGIOSPERMAE—DICOTYLEDONES sometimes so short that the stigma touched the anthers, and automatic self-pollina- tion consequently took place. Nyhuus found this latter form exclusively at greater elevations near Troms0 on the Dalfjeld, but the long-styled one predominated at stations of lowel level. Kerner says that the flower is at first adapted for crossing, but later on, when the secretion of nectar has ceased, pollination by wind becomes possible. When the style and anthers fade, the pollen which has not yet been removed by insects falls out of the anther-lobes, and is blown away by the wind in little clouds to the still receptive stigmas of younger flowers. Visitors.—The following were recorded by the observers, and for the localities mentioned.— Herm. Miiller (Alps), 3 humble-bees and 2 Lepidoptera (unbidden guests). Lindman (Alps), humble-bees. MacLeod (Pyrenees), a humble-bee (Bot. Jaarb. Dodonaea, Ghent, iii, 1891, p. 313). Schletterer and von Dalla Torre (Tyrol), the humble-bee Bombus alticola Krchb. 5 and 5, tolerably freq. 673. Euphrasia L. Dichogamous, mostly protogynous bee flowers; with concealed nectar, secreted by the lower part of the ovary and stored in the bottom of the Fig. 317. Euphrasia Odontites, /.. (after Herm. Miiller). (i) Bud with widely exserted stigma. (2) Flower with stiffma near the anthers. (3) Flower with style that has grown far beyond the anthers. (4) Flower with a lateral style (x 3J). (5) The two left stamens, seen from the inner side. (6) Ovary (X 7). a, base of the corolla; b, nectary ; r, upper, hairy part of the ovary ; d, style ; e, hairs which bind the anthers together; f, hairs (sprinkling-hairs) which prevent lateral dispersal of the falling pollen; g, prickles which prevent bees from inserting their proboscis between the lower parts of the filaments; k, place w
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