. La pollinisation des fleurs de manuel : d'après Hermann Mu ?ller 'le travail de la fécondation des fleurs par les insectes" . La fertilisation des plantes. 4-ANGIOSPERMES DICOTYLEDONES ' Il est très intéressant d'observer comment les différents types d'adaptation qui sont associés dans le plus grand ordre de plantes, la famille des Composées, rendant leurs fleurs " le plus réussi de toutes les fleurs," sont toutes illustrées dans les divers genres d'Asteraceae. Comme tous les seconds le composées sont nettement protandres, et les deux ordres d'accord dans la façon dont le pollen est déposé sur l'ou

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. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. 4 ANGIOSPERMAE—DICOTYLEDONES ' It is very interesting to observe how the various kinds of adaptation which are associated in the largest order of flowering plants, the Compositae, making their blossoms " the most successful of all flowers, " are individually illustrated in the various genera of Campanulaceae. Like all of the latter the Compositae are markedly protandrous, and the two orders agree in the way in which the pollen is deposited on the outside of the style to be carried away by insects, as also in the bending back of the stigmatic branches to the pollen-bearing region of the style so as to make automatic self-pollination possible. The aggregation of numerous small flowers into a head surrounded by an involucre is exemplified by Phyteuma and Jasione, which also agree with the Cympositae in the general accessibility of their nectar, and the free projection of the reproductive organs from the flowers. The union of anthers into a tube surrounding the style is indicated in Jasione, and completely effected in Symphandra. The tubular character of the lower part of the corolla, which in so many Compositae facilitates the ascent of nectar is exemplified by Trachelium, and the annular nectary surrounding the base of the style is found in Adenophora.' 510. Campanula L. As Sprengel emphasized long since ('Entd. Geh., ' pp. 109-13), species with flowers of the most various size agree in exhibiting marked protandry, and Hermann IMiiller adds that bees are particularly common visitors (' Fertilisation, ' pp. 366-7).. FJG. 212. Canipaiiiila f^itsiHa, Haenkc (after Herm. Rliiller). A. Longitudinal section of a j'ouna bud. B. Reproductive or(, rans of a bud ready to open. C. Ditto, of a flower in the first (male) stape. D. Ditto, of one in the second (female) stage, a^ anthers; co, corolla ; ;f, Clatnrnts ; ^r, style ; P'r^, styl