Page:The Journal of Indian Botany, Volume III.djvu/85

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It is a matter of common knowledge that, among 'tendril-climbers’, there are some plants, in which portions of tendrils are modified into ‘anchoring pads’ more commonly known as adhesive discs’. In ordinary text-books we often find Ampelopsis qainquefolia Michx. ("Vitis hederacea Ehrh.), a native of N. America, and A. Veitchii Hort. ( "Vitis inconstans Miq.), a native of Japan, commonly quoted as examples of such disc-bearing plants. But, it should by no means be concluded therefrom that, such ‘ pads * or ‘discs’ are restricted to the tendrils of some species of Vitis (N. O. Ampelideae) only. As a matter of fact, such ‘ pads 5 or ‘ discs ’ have been noticed in some plants belonging to different natural orders e.g. Cucurbitaceae and Bignoniaceae as well. Darwin, in his very interesting book.-— ‘ The Movements and Habits of Climbing Plants,* has dealt in a masterly way with some of these plants.

In the present paper it is, therefore, proposed to confine the author’s observations principally to the anchoring pads met with in the tendrils of Gymnopetalum cochinchinense Kurz and incidentally to a few other plants belonging to the natural order Cucurbitaceae. These observations are likely to prove interesting in view of the fact that, the majority of the plants mentioned here, being confined chiefly to the tropics, do not seem to have been studied by the previous workers viz: Darwin, Uhl worm, Goebel, Haberlandt, Yasuda and others. The author has, for reasons mentioned below, preferred to call these structures here as ‘anchoring pads’ instead of ‘adhesive discs.’ The term disc ’ seem to connote the idea of a flat circular surface as we find in the tendrils of Ampelopsis qainquefolia Michx. = Vitis hederacea Ehrh.) and V. assamica Laws.

The mature tendrils of Gymnopetalum Cochinchinense are usually branched (see fig. A) and it is on the apical and sub-apical regions of these arms that the anchoring pads are found to develop.