Note 25 — PHYSIOGNOMY OF PLANTS.

p. 26.—“Lianes, rope-plants, (‘Bush ropes;’ in Spanish, Vejuccos.”)

According to Kunth’s division of the Bauhinieæ, the true genus Bauhinia belongs to the New Continent: the African Bauhinia, B. rufescens, (Lam.) is a Pauletia (Cav.) a genus of which we found some new species in South America. So also the Banisterias, from among the Malpighiaceæ, are properly an American form; although two species are natives of India, and one species, Banisteria leona, described by Cavanilles, is a native of Western Africa. Within the tropics and in the Southern Hemisphere we find among the most different families of plants the twining rope-like climbers which in those regions render the forests at once so impenetrable to man, and on the other hand so accessible and habitable to the Quadrumanæ (or Monkeys) and to the Cercoleptes and the small tiger-cats. The rapid ascent to the tops of lofty trees, the passage from tree to tree, and even the crossing of streams by whole herds or troops of gregarious animals, are all greatly facilitated by these twining plants or Lianes.

In the South of Europe and in North America, Hops from among the Urticeæ, and the species of Vitis from among the Ampelideæ, belong to the class of twining climbers, and between the tropics we find climbing Grasses or Gramineæ. We have seen in the plains of Bogota, in the pass of Quindiu, in the Andes, and in the Quina-producing forests of Loxa, a Bambusacea allied to Nastus, our Chusquea scandens, twine round massive and lofty trunks of trees adorned at the same time with flowering Orchideæ. The Bambusa scandens (Tjankorreh), which Blume found in Java, belongs probably either to the genus Nastus or to that of Chusquea, the Carrizo of the Spanish settlers. Twining plants appear to me to be entirely absent in the Pine-woods of Mexico, but in New Zealand, besides the Ripogonum parviflorum of Robert Brown, (a climber belonging to the Smilaceæ which renders the forests almost impenetrable), the sweet-smelling Freycinetia Banksii, which belongs to the Pandaneæ, twines round a gigantic Podocarpus 220 English feet high, the P. dacryoides (Rich), called in the native language Kakikatea. (Dieffenbach, Travels in New Zealand, 1843, Vol. i. p. 426.)

With climbing Gramineæ and Pandaneæ are contrasted by their beautiful and many-coloured blossoms the Passifloras (among which, however, we even found an arborescent self-supporting species, Passiflora glauca, growing in the Andes of Popayan, at an elevation of 9840 French (10487 English) feet);—the Bignoniaceæ, Mutisias, Alströmerias, Urvilleæ, and Aristolochias. Among the latter our Aristolochia cordata has a crimson-coloured flower of 17 English inches diameter! “flores gigantei, pueris mitræ instar inservientes.” Many of these twining plants have a peculiar physiognomy and appearance produced by the square shape of their stems, by flattenings not caused by any external pressure, and by riband-like wavings to and fro. Cross sections of Bignonias and Banisterias shew cruciform or mosaic figures produced by the mutual pressure and interpenetration of the stems which twine around each other. (See very accurate drawings in Adrien de Jussieu’s Cours de Botanique, p. 77-79, fig. 105-108.)