. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. 56 ANGIOSPERMAE—DICOTYLEDONES probing for nectar dust themselves with pollen. But as at the same time they touch the stigmas, automatic self-pollination necessarily takes place. According to Mac- Leod, however, the anthers have lost so much of their pollen as to render this difficult. Up to this time the outwardly bent styles alternate with the stamens, so that insect- visits are still able to effect crossing. MacLeod states that the stamens and styles ultim
. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. 56 ANGIOSPERMAE—DICOTYLEDONES probing for nectar dust themselves with pollen. But as at the same time they touch the stigmas, automatic self-pollination necessarily takes place. According to Mac- Leod, however, the anthers have lost so much of their pollen as to render this difficult. Up to this time the outwardly bent styles alternate with the stamens, so that insect- visits are still able to effect crossing. MacLeod states that the stamens and styles ultimately become so intertangled that automatic self-pollination is inevitable. Insect visitors dust their upper sides with pollen if they probe for nectar between the corolla and stamens, but get covered all over with it should they creep into the base of the flower between the stamens. The description of the method of pollination given by Schulz for the main form A. elongata does not entirely agree with the above account, possibly because it is sometimes difficult to distinguish between younger and older flowers. At first the styles bend outwards so as to touch the anthers, and as the flowers are homogamous autogamy is thus effected. The stamens first move inwards and then outwards. Towards the end of anthesis the styles and stamens become closely intertangled, but this does not lead to autogamy, for at this time there is Fig. Armeria, L. (from often no pollcn left, besidcs which the tips of the styles a photoerraph, x 4). A flower, . , , j ..^ after corolla, stamens, and styles frequently projcct Irom the tangled mass. Kerner asserts, have fallen off, seen from above, however, that automatic self-polliuation does take place Kz^ calyx-teeth; n, nve-radiate ^ nectary. at this Stage, Styles and stamens being thrown into intertwining spirals. Visitors.—Knuih observed the following.— North Frisian Is.—A. Coleoptera. i. Cantharis fusca L. (with its head in the flowers).
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