Page:An introduction to physiological and systematical botany (1st edition).djvu/354

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324
FUNCTIONS OF STAMENS AND PISTILS.

as in compound, and even umbelliferous flowers, to be reversed, for the pistils are invariably central, or internal, in every simple flower, and would therefore, if drawn out into a monoecious spike, be above the stamens.

Many curious contrivances of Nature serve to bring the anthers and stigmas together. In Gloriosa, Andr. Repos. t. 129, the style is bent, at a right angle from the very base, for this evident purpose. In Saxifraga, and Parnassia, Engl. Bot. t. 82, the stamens lean one or two at a time over the stigma, retiring after they have shed their pollen, and giving place to others; which wonderful œconomy is very striking in the garden Rue, Ruta gravæolens[errata 1], whose stout and firm filaments cannot be disturbed from the posture in which they may happen to be, and evince a spontaneous movement unaffected by external causes. The five filaments of the Celosia, Cock's-comb, are connected at their lower part by a membranous web, which in moist weather is relaxed, and the stamens spread for shelter under the concave lobes of the corolla. When the air is dry the con-

  1. Correction: gravæolens should be amended to graveolens