Page:An introduction to physiological and systematical botany (1st edition).djvu/255

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making several circumvolutions, by which they take hold of any thing in their way, and then assume a firmer texture. After accomplishing a certain number of turns in one direction, some tendrils have a power of twining subsequently the contrary way; many of them moreover are branched or compound, so that the chances of their meeting with a support are multiplied. The Vine, Vitis vinifera, the various species of Passion-flower, and the Pea or Vetch tribe afford good examples of spiral tendrils. The Virginian Creeper Hedera, or, as it ought to be called, Vitis quinquefolia, has branched tendrils, whose extremities adhere to the smoothest flint, like the fibres of Ivy. Gloriosa superba, Andr. Repos. t. 129, and Flagellaria indica, have a simple spiral tendril at the end of each leaf; for they belong to the Monocotyledones, the structure of whose whole herbage is generally of the most simple and compendious kind. The flower-stalks of Cardiospermum Halicacabum bear tendrils; but a most singular kind of tendril if it may so be called, which certainly has