Note 21 — PHYSIOGNOMY OF PLANTS.

p. 24.—“Orchideæ.”

The almost animal shape of blossoms of Orchideæ is particularly striking in the celebrated Torito of South America (our Anguloa grandiflora); in the Mosquito (our Restrepia antennifera); in the Flor del Espiritu Santo (also an Anguloa, according to Floræ Peruvianæ Prodrom. p. 118, tab. 26); in the ant-like flower of the Chiloglottis cornuta (Hooker, Flora antarctica, p. 69); in the Mexican Bletia speciosa; and in the highly curious host of our European species of Ophrys: O. muscifera, O. apifera, O. aranifera, O. arachnites, &c. A predilection for this superbly flowering group of plants has so increased, that the number cultivated in Europe by the brothers Loddiges in 1848 has been estimated at 2360 species; while in 1843 it was rather more than 1650, and in 1813 only 115. What a rich mine of still unknown superb flowering Orchideæ the interior of Africa must contain, if it is well watered! Lindley, in his fine work entitled “The Genera and Species of Orchideous Plants,” described in 1840 precisely 1980 species; at the end of the year 1848 Klotzsch reckoned 3545 species.

While in the temperate and cold zones there are only “terrestrial” Orchideæ, i. e. growing on and close to the ground, tropical countries possess both forms, i. e. the “terrestrial” and the “parasitic,” which grow on trunks of trees. To the first-named of these two divisions belong the tropical genera Neottia, Cranichis, and most of the Habenarias. We have also found both forms growing as alpine plants on the slopes of the chain of the Andes of New Granada and Quito: of the parasitical Orchideæ (Epidendreæ), Masdevallia uniflora (at 9600 French, or about 10230 English feet); Cyrtochilum flexuosum (at 9480 French, or about 10100 English feet); and Dendrobium aggregatum (8900 French, or about 9480 English feet): and of the terrestrial Orchideæ, the Altensteinia paleacea, near Lloa Chiquito, at the foot of the Volcano of Pichincha. Claude Gay thinks that the Orchideæ said to have been seen growing on trees in the Island of Juan Fernandez, and even in Chiloe, were probably in reality only parasitical Pourretias, which extend at least as far south as 40° S. lat. In New Zealand we find that the tropical form of Orchideæ hanging from trees extends even to 45° S. lat. The Orchideæ of Auckland’s and Campbell’s Islands, however (Chiloglottis, Thelymitra, and Acianthus), grow on the ground in moss. In the animal kingdom, one tropical form at least advances much farther to the south. In Macquarie Island, in lat. 54° 39´, nearer to the South Pole therefore than Dantsic is to the North Pole, there is a native parrot. (See also the section Orchideæ in my work de Distrib. geogr. Plant., pp. 241-247.)