Note 146 — Chapter IV · Tendril-Bearers—(continued).
Reading edition
Dr. M’Nab remarks (Trans. Bot. Soc. Edinburgh, vol xi. p. 292) that the tendrils of Amp. Veitchii bear small globular discs before they have came into contact with any object; and I have since observed the same fact. These discs, however, increase greatly in size, if they press against and adhere to any surface. The tendrils, therefore, of one species of Ampelopsis require the stimulus of contact for the first development of their discs, whilst those of another species do not need any such stimulus. We have seen an exactly parallel case with two species of Bignoniaceæ.