. The elements of botany for beginners and for schools. Botany. 114 FERTILIZATION. [SECTION 13. to both calyx-tube and ovary, as in Hawthorn (Fig. 273). A flattened hypogyuous disk, underlying the ovary or ovaries, and from which they fall away at maturity, is sometimes called a Gynobase, as in the Rue family. In some Borragineous flowers, such as Houndstongue, the gynobase runs up in the centre between the carpels into a carpophore. The so-called epigymus disk (or Stylopodiumj crowning the summit of the ovary in flowers of Urabelliferse, etc., cannot be said to belong to the receptacle. Secti
. The elements of botany for beginners and for schools. Botany. 114 FERTILIZATION. [SECTION 13. to both calyx-tube and ovary, as in Hawthorn (Fig. 273). A flattened hypogyuous disk, underlying the ovary or ovaries, and from which they fall away at maturity, is sometimes called a Gynobase, as in the Rue family. In some Borragineous flowers, such as Houndstongue, the gynobase runs up in the centre between the carpels into a carpophore. The so-called epigymus disk (or Stylopodiumj crowning the summit of the ovary in flowers of Urabelliferse, etc., cannot be said to belong to the receptacle. Section XIII. FERTILIZATION. 328. The end of the flower is attained when the ovules become seeds. A flower remains for a certain time (longer or shorter according to the species) in aaihesis, that is, in the proper state for the fulfilment of this end. During anthesis, the ovules have to be fertilized by the pollen; or at least some pollen has to reach the stigma, or in gymnospermy the ovule itself, and to set up the peculiar growth upon its moist and permeable tis- sue, which has for result the production of an embryo in the ovules. By this the ovules are said to be fertilized. The first step is pollination, or, so to say, the sowing of the proper pollen upon the stigma, where it is to germinate. § 1. ADAPTATIONS FOR POLLINATION OF THE STIGMA. 329. These various and ever-interesting adaptations and processes are illustrated in the "Botanical Text Book, Structural Botany," chap. VI. sect, iv., also in a brief and simple way in " Botany for Young People, How Plants ; So mere outlines only arc given here. 330. Sometimes the application of pollen to the stigma is left to chance, as in dioecious wind-fertilized flowers ; sometimes it is rendered very sure, as in flowers that are fertilized in the bud; sometimes the pollen is prevented from reaching the stigma of the same flower, although placed very near to it, but then there are always arrangements for its t
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