. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. 464 ANGIOSPERMAE—DICOTYLEDONES even in the third type (C), where hermaphrodite and female flowers are associated, for here the primary umbels possess but few male flowers, while in those which bloom last scarcely any others are present. Something has already been said about the geitonogamy that so frequently takes place among Umbelliferae (Vol. I, pp. 41-2). Kerner describes some very diverse arrangements of the kind ('Nat. Hist. PI.,' Eng. Ed. i, II, pp. 32
. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. 464 ANGIOSPERMAE—DICOTYLEDONES even in the third type (C), where hermaphrodite and female flowers are associated, for here the primary umbels possess but few male flowers, while in those which bloom last scarcely any others are present. Something has already been said about the geitonogamy that so frequently takes place among Umbelliferae (Vol. I, pp. 41-2). Kerner describes some very diverse arrangements of the kind ('Nat. Hist. PI.,' Eng. Ed. i, II, pp. 323-5). In the crowded capitula of Eryngium and Hacquetia, when the filaments elongate their pollen-covered anthers come into contact with the mature stigmas of neighbouring flowers, in consequence of the divergence of the styles. In Sanicula, Astrantia, and Laserpitium, there is a deviation from this form of geitonogamy owing to the fact that pollen flowers as well as hermaphrodite ones are present; but here again the same thing happens, because the elongating styles bend over and entangle themselves with adjacent flowers, so that their stigmas can take up pollen. The converse is true for Pachypleurum, where the stamens ultimately radiate in an almost stellate manner, and touch the mature stigmas of neighbouring flowers. The relations are similar in the case of Siler; while in Athamanta, Meum, and Chaerophyllum, hermaphrodite and pollen flowers are associated. After the stamens of the former have dehisced and fallen off, the pollen flowers ripen their anthers, and drop their pollen upon the still receptive stigmas of the originally hermaphrodite flowers. (Cf. Fig. 155 B.) For Anthriscus, Foeniculum, Coriandrum, Slum, and Ferulago, Kerner inflorescences of two kinds. The umbels that blossom first mostly contain her- maphrodite flowers, with a few scattered pollen flowers, while those which do so later contain only the latter kind. After the stamens of the protandrous
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